Adding upstream version 0.8.upstream/0.8

Signed-off-by: Daniel Baumann <mail@daniel-baumann.ch>

32 files changed, 3796 insertions, 1549 deletions

diff --git a/ChangeLog b/ChangeLog
index 85f7717..54282fe 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,19 @@
-2009-12-01  Antonio Diaz Diaz  <ant_diaz@teleline.es>
-
-	* Version 0.8-rc1 released.
+2010-11-15  Antonio Diaz Diaz  <ant_diaz@teleline.es>
+
+	* Version 0.8 released.
+	* main.cc: Added new options "--zcat", "--zgrep" and "--ztest".
+	* zcat.cc: New file implementing zcat+cat functionality in C++.
+	* zcmp.cc: New file implementing zcmp+cmp functionality in C++.
+	* doc/zcmp.1: New file.
+	* zcmp.in: Removed.
+	* zdiff.cc: New file implementing zdiff functionality in C++.
+	* zdiff.in: Removed.
+	* zgrep.cc: New file implementing zgrep functionality in C++.
+	* All mentions to zegrep and zfgrep have been removed from the
+	  documentation because egrep and fgrep are deprecated.
+	* ztest.cc: New file implementing ztest functionality in C++.
+	* Makefile.in: Added quotes to directory names.
+	* testsuite/check.sh: Use "test.txt" instead of "COPYING" for testing.
 	* Removed environment safeguards from configure as requested by
 	  Richard Stallman. Now environment variables affect configure.
 
@@ -46,8 +59,8 @@
 	* Version 0.1 released.
 
 
-Copyright (C) 2009 Antonio Diaz Diaz.
+Copyright (C) 2009, 2010 Antonio Diaz Diaz.
 
 This file is a collection of facts, and thus it is not copyrightable,
-but just in case, I give you unlimited permission to copy, distribute
-and modify it.
+but just in case, you have unlimited permission to copy, distribute and
+modify it.
diff --git a/INSTALL b/INSTALL
index 1dadb5e..9c7b683 100644
--- a/INSTALL
+++ b/INSTALL
@@ -55,7 +55,7 @@ After running `configure', you can run `make' and `make install' as
 explained above.
 
 
-Copyright (C) 2009 Antonio Diaz Diaz.
+Copyright (C) 2009, 2010 Antonio Diaz Diaz.
 
 This file is free documentation: you have unlimited permission to copy,
 distribute and modify it.
diff --git a/Makefile.in b/Makefile.in
index edaf42f..4a04228 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -1,5 +1,5 @@
 
-DISTNAME = $(progname)-$(progversion)
+DISTNAME = $(pkgname)-$(pkgversion)
 INSTALL = install
 INSTALL_PROGRAM = $(INSTALL) -p -m 755
 INSTALL_SCRIPT = $(INSTALL) -p -m 755
@@ -7,33 +7,33 @@ INSTALL_DATA = $(INSTALL) -p -m 644
 INSTALL_DIR = $(INSTALL) -d -m 755
 SHELL = /bin/sh
 
-objs = arg_parser.o main.o
-scripts = zcat zcmp zdiff zegrep zfgrep zgrep ztest
+objs = arg_parser.o zutils.o main.o
+zcmp_objs = arg_parser.o zutils.o zcmp.o
+zdiff_objs = arg_parser.o zutils.o zdiff.o
+scripts = zcat zegrep zfgrep zgrep ztest
 
 
 .PHONY : all install install-info install-man install-strip \
          uninstall uninstall-info uninstall-man \
          doc info man check dist clean distclean
 
-all : $(progname) $(scripts)
+all : $(progname) zcmp zdiff $(scripts)
 
 $(progname) : $(objs)
-	$(CXX) $(LDFLAGS) -o $(progname) $(objs)
+	$(CXX) $(LDFLAGS) -o $@ $(objs)
 
 $(progname)_profiled : $(objs)
-	$(CXX) $(LDFLAGS) -pg -o $(progname)_profiled $(objs)
+	$(CXX) $(LDFLAGS) -pg -o $@ $(objs)
 
 zcat : zcat.in
-	sed -e 's,VERSION,$(progversion),g' $(VPATH)/zcat.in > zcat
+	cat $(VPATH)/zcat.in > zcat
 	chmod a+x zcat
 
-zcmp : zcmp.in
-	cat $(VPATH)/zcmp.in > zcmp
-	chmod a+x zcmp
+zcmp : $(zcmp_objs)
+	$(CXX) $(LDFLAGS) -o $@ $(zcmp_objs)
 
-zdiff : zdiff.in
-	sed -e 's,VERSION,$(progversion),g' $(VPATH)/zdiff.in > zdiff
-	chmod a+x zdiff
+zdiff : $(zdiff_objs)
+	$(CXX) $(LDFLAGS) -o $@ $(zdiff_objs)
 
 zegrep : zegrep.in
 	cat $(VPATH)/zegrep.in > zegrep
@@ -44,15 +44,15 @@ zfgrep : zfgrep.in
 	chmod a+x zfgrep
 
 zgrep : zgrep.in
-	sed -e 's,VERSION,$(progversion),g' $(VPATH)/zgrep.in > zgrep
+	cat $(VPATH)/zgrep.in > zgrep
 	chmod a+x zgrep
 
 ztest : ztest.in
-	sed -e 's,VERSION,$(progversion),g' $(VPATH)/ztest.in > ztest
+	cat $(VPATH)/ztest.in > ztest
 	chmod a+x ztest
 
-main.o : main.cc
-	$(CXX) $(CPPFLAGS) $(CXXFLAGS) -DPROGVERSION=\"$(progversion)\" -c -o $@ $<
+zutils.o : zutils.cc
+	$(CXX) $(CPPFLAGS) $(CXXFLAGS) -DPROGVERSION=\"$(pkgversion)\" -c -o $@ $<
 
 %.o : %.cc
 	$(CXX) $(CPPFLAGS) $(CXXFLAGS) -c -o $@ $<
@@ -60,96 +60,100 @@ main.o : main.cc
 $(objs)      : Makefile
 $(scripts)   : Makefile
 arg_parser.o : arg_parser.h
-main.o       : arg_parser.h
+main.o       : arg_parser.h zutils.h zcat.cc zgrep.cc ztest.cc
+zcmp.o       : arg_parser.h zutils.h Makefile
+zdiff.o      : arg_parser.h zutils.h Makefile
+zutils.o     : zutils.h
 
 doc : info man
 
-info : $(VPATH)/doc/$(progname).info
+info : $(VPATH)/doc/$(pkgname).info
 
-$(VPATH)/doc/$(progname).info : $(VPATH)/doc/$(progname).texinfo
-	cd $(VPATH)/doc && makeinfo $(progname).texinfo
+$(VPATH)/doc/$(pkgname).info : $(VPATH)/doc/$(pkgname).texinfo
+	cd $(VPATH)/doc && makeinfo $(pkgname).texinfo
 
-man : $(VPATH)/doc/zcat.1 $(VPATH)/doc/zdiff.1 \
+man : $(VPATH)/doc/zcat.1 $(VPATH)/doc/zcmp.1 $(VPATH)/doc/zdiff.1 \
       $(VPATH)/doc/zgrep.1 $(VPATH)/doc/ztest.1
 
-$(VPATH)/doc/zcat.1 : zcat
-	help2man -n 'concatenate compressed files to stdout' \
-	  -o $(VPATH)/doc/zcat.1 --no-info ./zcat
+$(VPATH)/doc/zcat.1 : $(progname) zcat
+	help2man -n 'decompress and concatenate files to standard output' \
+	  -o $@ --no-info ./zcat
+
+$(VPATH)/doc/zcmp.1 : zcmp
+	help2man -n 'decompress and compare two files byte by byte' \
+	  -o $@ --no-info ./zcmp
 
 $(VPATH)/doc/zdiff.1 : zdiff
-	help2man -n 'compare compressed files' \
-	  -o $(VPATH)/doc/zdiff.1 --no-info ./zdiff
+	help2man -n 'decompress and compare two files line by line' \
+	  -o $@ --no-info ./zdiff
 
-$(VPATH)/doc/zgrep.1 : zgrep
+$(VPATH)/doc/zgrep.1 : $(progname) zgrep
 	help2man -n 'search compressed files for a regular expression' \
-	  -o $(VPATH)/doc/zgrep.1 --no-info ./zgrep
+	  -o $@ --no-info ./zgrep
 
-$(VPATH)/doc/ztest.1 : ztest
+$(VPATH)/doc/ztest.1 : $(progname) ztest
 	help2man -n 'verify integrity of compressed files' \
-	  -o $(VPATH)/doc/ztest.1 --no-info ./ztest
+	  -o $@ --no-info ./ztest
 
 Makefile : $(VPATH)/configure $(VPATH)/Makefile.in
 	./config.status
 
-check : all $(VPATH)/testsuite/check.sh
-	@$(VPATH)/testsuite/check.sh $(VPATH)/testsuite
+check : all
+	@$(VPATH)/testsuite/check.sh $(VPATH)/testsuite $(pkgversion)
 
 install : all install-info install-man
-	if [ ! -d $(DESTDIR)$(bindir) ] ; then $(INSTALL_DIR) $(DESTDIR)$(bindir) ; fi
-	$(INSTALL_PROGRAM) ./$(progname) $(DESTDIR)$(bindir)/$(progname)
-	$(INSTALL_SCRIPT) zcat $(DESTDIR)$(bindir)/zcat
-	$(INSTALL_SCRIPT) zcmp $(DESTDIR)$(bindir)/zcmp
-	$(INSTALL_SCRIPT) zdiff $(DESTDIR)$(bindir)/zdiff
-	$(INSTALL_SCRIPT) zegrep $(DESTDIR)$(bindir)/zegrep
-	$(INSTALL_SCRIPT) zfgrep $(DESTDIR)$(bindir)/zfgrep
-	$(INSTALL_SCRIPT) zgrep $(DESTDIR)$(bindir)/zgrep
-	$(INSTALL_SCRIPT) ztest $(DESTDIR)$(bindir)/ztest
+	if [ ! -d "$(DESTDIR)$(bindir)" ] ; then $(INSTALL_DIR) "$(DESTDIR)$(bindir)" ; fi
+	$(INSTALL_PROGRAM) ./$(progname) "$(DESTDIR)$(bindir)/$(progname)"
+	$(INSTALL_SCRIPT) ./zcat "$(DESTDIR)$(bindir)/zcat"
+	$(INSTALL_PROGRAM) ./zcmp "$(DESTDIR)$(bindir)/zcmp"
+	$(INSTALL_PROGRAM) ./zdiff "$(DESTDIR)$(bindir)/zdiff"
+	$(INSTALL_SCRIPT) ./zegrep "$(DESTDIR)$(bindir)/zegrep"
+	$(INSTALL_SCRIPT) ./zfgrep "$(DESTDIR)$(bindir)/zfgrep"
+	$(INSTALL_SCRIPT) ./zgrep "$(DESTDIR)$(bindir)/zgrep"
+	$(INSTALL_SCRIPT) ./ztest "$(DESTDIR)$(bindir)/ztest"
 
 install-info :
-	if [ ! -d $(DESTDIR)$(infodir) ] ; then $(INSTALL_DIR) $(DESTDIR)$(infodir) ; fi
-	$(INSTALL_DATA) $(VPATH)/doc/$(progname).info $(DESTDIR)$(infodir)/$(progname).info
-	-install-info --info-dir=$(DESTDIR)$(infodir) $(DESTDIR)$(infodir)/$(progname).info
+	if [ ! -d "$(DESTDIR)$(infodir)" ] ; then $(INSTALL_DIR) "$(DESTDIR)$(infodir)" ; fi
+	$(INSTALL_DATA) $(VPATH)/doc/$(pkgname).info "$(DESTDIR)$(infodir)/$(pkgname).info"
+	-install-info --info-dir="$(DESTDIR)$(infodir)" $(DESTDIR)$(infodir)/$(pkgname).info
 
 install-man :
-	if [ ! -d $(DESTDIR)$(mandir)/man1 ] ; then $(INSTALL_DIR) $(DESTDIR)$(mandir)/man1 ; fi
-	$(INSTALL_DATA) $(VPATH)/doc/zcat.1 $(DESTDIR)$(mandir)/man1/zcat.1
-	-rm -f $(DESTDIR)$(mandir)/man1/zcmp.1
-	cd $(DESTDIR)$(mandir)/man1 && ln -s zdiff.1 zcmp.1
-	$(INSTALL_DATA) $(VPATH)/doc/zdiff.1 $(DESTDIR)$(mandir)/man1/zdiff.1
-	$(INSTALL_DATA) $(VPATH)/doc/zgrep.1 $(DESTDIR)$(mandir)/man1/zgrep.1
-	-rm -f $(DESTDIR)$(mandir)/man1/zegrep.1
-	-rm -f $(DESTDIR)$(mandir)/man1/zfgrep.1
-	cd $(DESTDIR)$(mandir)/man1 && ln -s zgrep.1 zegrep.1
-	cd $(DESTDIR)$(mandir)/man1 && ln -s zgrep.1 zfgrep.1
-	$(INSTALL_DATA) $(VPATH)/doc/ztest.1 $(DESTDIR)$(mandir)/man1/ztest.1
+	if [ ! -d "$(DESTDIR)$(mandir)/man1" ] ; then $(INSTALL_DIR) "$(DESTDIR)$(mandir)/man1" ; fi
+	$(INSTALL_DATA) $(VPATH)/doc/zcat.1 "$(DESTDIR)$(mandir)/man1/zcat.1"
+	$(INSTALL_DATA) $(VPATH)/doc/zcmp.1 "$(DESTDIR)$(mandir)/man1/zcmp.1"
+	$(INSTALL_DATA) $(VPATH)/doc/zdiff.1 "$(DESTDIR)$(mandir)/man1/zdiff.1"
+	$(INSTALL_DATA) $(VPATH)/doc/zgrep.1 "$(DESTDIR)$(mandir)/man1/zgrep.1"
+	-rm -f "$(DESTDIR)$(mandir)/man1/zegrep.1"
+	-rm -f "$(DESTDIR)$(mandir)/man1/zfgrep.1"
+	$(INSTALL_DATA) $(VPATH)/doc/ztest.1 "$(DESTDIR)$(mandir)/man1/ztest.1"
 
 install-strip : all
 	$(MAKE) INSTALL_PROGRAM='$(INSTALL_PROGRAM) -s' install
 
 uninstall : uninstall-info uninstall-man
-	-rm -f $(DESTDIR)$(bindir)/$(progname)
-	-rm -f $(DESTDIR)$(bindir)/zcat
-	-rm -f $(DESTDIR)$(bindir)/zcmp
-	-rm -f $(DESTDIR)$(bindir)/zdiff
-	-rm -f $(DESTDIR)$(bindir)/zegrep
-	-rm -f $(DESTDIR)$(bindir)/zfgrep
-	-rm -f $(DESTDIR)$(bindir)/zgrep
-	-rm -f $(DESTDIR)$(bindir)/ztest
+	-rm -f "$(DESTDIR)$(bindir)/$(progname)"
+	-rm -f "$(DESTDIR)$(bindir)/zcat"
+	-rm -f "$(DESTDIR)$(bindir)/zcmp"
+	-rm -f "$(DESTDIR)$(bindir)/zdiff"
+	-rm -f "$(DESTDIR)$(bindir)/zegrep"
+	-rm -f "$(DESTDIR)$(bindir)/zfgrep"
+	-rm -f "$(DESTDIR)$(bindir)/zgrep"
+	-rm -f "$(DESTDIR)$(bindir)/ztest"
 
 uninstall-info :
-	-install-info --info-dir=$(DESTDIR)$(infodir) --remove $(DESTDIR)$(infodir)/$(progname).info
-	-rm -f $(DESTDIR)$(infodir)/$(progname).info
+	-install-info --info-dir="$(DESTDIR)$(infodir)" --remove "$(DESTDIR)$(infodir)/$(pkgname).info"
+	-rm -f "$(DESTDIR)$(infodir)/$(pkgname).info"
 
 uninstall-man :
-	-rm -f $(DESTDIR)$(mandir)/man1/zcat.1
-	-rm -f $(DESTDIR)$(mandir)/man1/zcmp.1
-	-rm -f $(DESTDIR)$(mandir)/man1/zdiff.1
-	-rm -f $(DESTDIR)$(mandir)/man1/zegrep.1
-	-rm -f $(DESTDIR)$(mandir)/man1/zfgrep.1
-	-rm -f $(DESTDIR)$(mandir)/man1/zgrep.1
-	-rm -f $(DESTDIR)$(mandir)/man1/ztest.1
-
-dist :
+	-rm -f "$(DESTDIR)$(mandir)/man1/zcat.1"
+	-rm -f "$(DESTDIR)$(mandir)/man1/zcmp.1"
+	-rm -f "$(DESTDIR)$(mandir)/man1/zdiff.1"
+	-rm -f "$(DESTDIR)$(mandir)/man1/zegrep.1"
+	-rm -f "$(DESTDIR)$(mandir)/man1/zfgrep.1"
+	-rm -f "$(DESTDIR)$(mandir)/man1/zgrep.1"
+	-rm -f "$(DESTDIR)$(mandir)/man1/ztest.1"
+
+dist : doc
 	ln -sf $(VPATH) $(DISTNAME)
 	tar -cvf $(DISTNAME).tar \
 	  $(DISTNAME)/AUTHORS \
@@ -161,9 +165,10 @@ dist :
 	  $(DISTNAME)/README \
 	  $(DISTNAME)/configure \
 	  $(DISTNAME)/doc/*.1 \
-	  $(DISTNAME)/doc/$(progname).info \
-	  $(DISTNAME)/doc/$(progname).texinfo \
+	  $(DISTNAME)/doc/$(pkgname).info \
+	  $(DISTNAME)/doc/$(pkgname).texinfo \
 	  $(DISTNAME)/testsuite/check.sh \
+	  $(DISTNAME)/testsuite/test.txt \
 	  $(DISTNAME)/*.h \
 	  $(DISTNAME)/*.cc \
 	  $(DISTNAME)/z*.in
@@ -172,7 +177,7 @@ dist :
 
 clean :
 	-rm -f $(progname) $(progname)_profiled $(objs)
-	-rm -f $(scripts)
+	-rm -f zcmp zcmp.o zdiff zdiff.o $(scripts)
 
 distclean : clean
 	-rm -f Makefile config.status *.tar *.tar.lz
diff --git a/NEWS b/NEWS
index 66001d3..cf6500b 100644
--- a/NEWS
+++ b/NEWS
@@ -1,4 +1,15 @@
 Changes in version 0.8:
 
+The option "--recursive" has been added to zgrep.
+
+All the utilities have been rewritten in C++, making them safer and more
+efficient.
+
+Zcat and zcmp implement the functionality of cat and cmp respectively.
+Cat and cmp are not needed at runtime.
+
+All mentions to zegrep and zfgrep have been removed from the
+documentation because egrep and fgrep are deprecated.
+
 Environment safeguards from configure have been removed. This allows
 environment variables to affect configuration.
diff --git a/README b/README
index 2550b69..a94268b 100644
--- a/README
+++ b/README
@@ -1,18 +1,22 @@
 Description
 
-Zutils is a collection of utilities for dealing with any combination of
-compressed and non-compressed files transparently. The supported
-compressors are bzip2, gzip, lzip and xz.
+Zutils is a collection of utilities able to deal with any combination of
+compressed and non-compressed files transparently. If any given file,
+including standard input, is compressed, its uncompressed content is
+used. Compressed files are decompressed on the fly; no temporary files
+are created. These utilities are not wrapper scripts but safer and more
+efficient C++ programs. In particular the "--recursive" option is very
+efficient in those utilities supporting it.
 
-The currently provided utilities are zcat, zcmp, zdiff, zegrep, zfgrep,
-zgrep and ztest.
+The provided utilities are zcat, zcmp, zdiff, zgrep and ztest.
+The supported compressors are bzip2, gzip, lzip and xz.
 
 
-Copyright (C) 2009 Antonio Diaz Diaz.
+Copyright (C) 2009, 2010 Antonio Diaz Diaz.
 
 This file is free documentation: you have unlimited permission to copy,
 distribute and modify it.
 
 The file Makefile.in is a data file used by configure to produce the
-Makefile. It has the same copyright owner and permissions that this
-file.
+Makefile. It has the same copyright owner and permissions that configure
+itself.
diff --git a/arg_parser.cc b/arg_parser.cc
index b889e1a..cc9f87d 100644
--- a/arg_parser.cc
+++ b/arg_parser.cc
@@ -1,18 +1,28 @@
-/*  Arg_parser - A POSIX/GNU command line argument parser.
-    Copyright (C) 2006, 2007, 2008, 2009 Antonio Diaz Diaz.
+/*  Arg_parser - A POSIX/GNU command line argument parser. (C++ version)
+    Copyright (C) 2006, 2007, 2008, 2009, 2010 Antonio Diaz Diaz.
 
-    This program is free software: you can redistribute it and/or modify
+    This library is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation, either version 3 of the License, or
     (at your option) any later version.
 
-    This program is distributed in the hope that it will be useful,
+    This library is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
 
     You should have received a copy of the GNU General Public License
-    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+    along with this library.  If not, see <http://www.gnu.org/licenses/>.
+
+    As a special exception, you may use this file as part of a free
+    software library without restriction.  Specifically, if other files
+    instantiate templates or use macros or inline functions from this
+    file, or you compile this file and link it with other files to
+    produce an executable, this file does not by itself cause the
+    resulting executable to be covered by the GNU General Public
+    License.  This exception does not however invalidate any other
+    reasons why the executable file might be covered by the GNU General
+    Public License.
 */
 
 #include <cstring>
diff --git a/arg_parser.h b/arg_parser.h
index fa6161b..da1cc94 100644
--- a/arg_parser.h
+++ b/arg_parser.h
@@ -1,18 +1,28 @@
-/*  Arg_parser - A POSIX/GNU command line argument parser.
-    Copyright (C) 2006, 2007, 2008, 2009 Antonio Diaz Diaz.
+/*  Arg_parser - A POSIX/GNU command line argument parser. (C++ version)
+    Copyright (C) 2006, 2007, 2008, 2009, 2010 Antonio Diaz Diaz.
 
-    This program is free software: you can redistribute it and/or modify
+    This library is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation, either version 3 of the License, or
     (at your option) any later version.
 
-    This program is distributed in the hope that it will be useful,
+    This library is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
 
     You should have received a copy of the GNU General Public License
-    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+    along with this library.  If not, see <http://www.gnu.org/licenses/>.
+
+    As a special exception, you may use this file as part of a free
+    software library without restriction.  Specifically, if other files
+    instantiate templates or use macros or inline functions from this
+    file, or you compile this file and link it with other files to
+    produce an executable, this file does not by itself cause the
+    resulting executable to be covered by the GNU General Public
+    License.  This exception does not however invalidate any other
+    reasons why the executable file might be covered by the GNU General
+    Public License.
 */
 
 /*  Arg_parser reads the arguments in `argv' and creates a number of
diff --git a/configure b/configure
index c94a506..2a45a9a 100755
--- a/configure
+++ b/configure
@@ -1,17 +1,18 @@
 #! /bin/sh
 # configure script for Zutils - Utilities dealing with compressed files
-# Copyright (C) 2009 Antonio Diaz Diaz.
+# Copyright (C) 2009, 2010 Antonio Diaz Diaz.
 #
 # This configure script is free software: you have unlimited permission
 # to copy, distribute and modify it.
 #
-# Date of this version: 2009-12-01
+# Date of this version: 2010-11-15
 
 args=
 no_create=
+pkgname=zutils
+pkgversion=0.8
 progname=zutils
-progversion=0.8-rc1
-srctrigger=zdiff.in
+srctrigger=zutils.h
 
 # clear some things potentially inherited from environment.
 LC_ALL=C
@@ -69,7 +70,7 @@ while [ -n "$1" ] ; do
 		echo
 		exit 0 ;;
 	--version | --ve* | -V)
-		echo "Configure script for ${progname} version ${progversion}"
+		echo "Configure script for ${pkgname} version ${pkgversion}"
 		exit 0 ;;
 	--srcdir* | --sr*)
 		srcdir=`echo ${optarg} | sed -e 's,/$,,'` ;;
@@ -81,7 +82,7 @@ while [ -n "$1" ] ; do
 		bindir=`echo ${optarg} | sed -e 's,/$,,'` ;;
 	--datadir* | --da*)
 		datadir=`echo ${optarg} | sed -e 's,/$,,'` ;;
-	--infodir* | --in*)
+	--infodir* | --inf*)
 		infodir=`echo ${optarg} | sed -e 's,/$,,'` ;;
 	--mandir* | --ma*)
 		mandir=`echo ${optarg} | sed -e 's,/$,,'` ;;
@@ -136,7 +137,7 @@ if [ -z "${CXX}" ] ; then		# Let the user override the test.
 fi
 
 echo
-if [ x${no_create} = x ] ; then
+if [ -z "${no_create}" ] ; then
 	echo "creating config.status"
 	rm -f config.status
 	cat > config.status << EOF
@@ -168,14 +169,15 @@ echo "LDFLAGS = ${LDFLAGS}"
 rm -f Makefile
 cat > Makefile << EOF
 # Makefile for Zutils - Utilities dealing with compressed files
-# Copyright (C) 2009 Antonio Diaz Diaz.
+# Copyright (C) 2009, 2010 Antonio Diaz Diaz.
 # This file was generated automatically by configure. Do not edit.
 #
 # This Makefile is free software: you have unlimited permission
 # to copy, distribute and modify it.
 
+pkgname = ${pkgname}
+pkgversion = ${pkgversion}
 progname = ${progname}
-progversion = ${progversion}
 VPATH = ${srcdir}
 prefix = ${prefix}
 exec_prefix = ${exec_prefix}
diff --git a/doc/zcat.1 b/doc/zcat.1
index 407e270..244aaad 100644
--- a/doc/zcat.1
+++ b/doc/zcat.1
@@ -1,25 +1,22 @@
-.\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.36.
-.TH ZCAT "1" "December 2009" "Zcat (zutils) 0.8-rc1" "User Commands"
+.\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.37.1.
+.TH ZCAT "1" "November 2010" "Zcat (zutils) 0.8" "User Commands"
 .SH NAME
-Zcat \- concatenate compressed files to stdout
+Zcat \- decompress and concatenate files to standard output
 .SH SYNOPSIS
 .B zcat
-[\fIOPTIONS\fR] [\fICAT_OPTIONS\fR] [\fIFILES\fR]
+[\fIoptions\fR] [\fIfiles\fR]
 .SH DESCRIPTION
-Zcat \- Cat wrapper for compressed files.
-.PP
-Zcat is a wrapper script around the cat command that allows transparent
-concatenation of any combination of compressed and non\-compressed files.
-If any given file is compressed, its uncompressed content is used. If a
-given file does not exist, zcat tries the compressed file names
+Zcat copies each given file ("\-" means standard input), to standard
+output. If any given file is compressed, its uncompressed content is
+used. If a given file does not exist, and its name does not end with one
+of the known extensions, zcat tries the compressed file names
 corresponding to the supported compressors. If no files are specified,
 data is read from standard input, decompressed if needed, and sent to
-stdout. Data read from standard input must be of the same type; all
-uncompressed or all compressed with the same compressor.
+standard output. Data read from standard input must be of the same type;
+all uncompressed or all compressed with the same compressor.
 The supported compressors are bzip2, gzip, lzip and xz.
 .PP
-CAT_OPTIONS are passed directly to cat.
-The exit status from cat is preserved.
+Exit status is 0 if no errors occurred, 1 otherwise.
 .SH OPTIONS
 .TP
 \fB\-h\fR, \fB\-\-help\fR
@@ -28,12 +25,48 @@ display this help and exit
 \fB\-V\fR, \fB\-\-version\fR
 output version information and exit
 .TP
+\fB\-A\fR, \fB\-\-show\-all\fR
+equivalent to `\-vET'
+.TP
+\fB\-b\fR, \fB\-\-number\-nonblank\fR
+number nonblank output lines
+.TP
+\fB\-e\fR
+equivalent to `\-vE'
+.TP
+\fB\-E\fR, \fB\-\-show\-ends\fR
+display `$' at end of each line
+.TP
+\fB\-n\fR, \fB\-\-number\fR
+number all output lines
+.TP
+\fB\-q\fR, \fB\-\-quiet\fR
+suppress all messages
+.TP
 \fB\-r\fR, \fB\-\-recursive\fR
 operate recursively on directories
+.TP
+\fB\-s\fR, \fB\-\-squeeze\-blank\fR
+never more than one single blank line
+.TP
+\fB\-t\fR
+equivalent to `\-vT'
+.TP
+\fB\-T\fR, \fB\-\-show\-tabs\fR
+display TAB characters as `^I'
+.TP
+\fB\-v\fR, \fB\-\-show\-nonprinting\fR
+use `^' and `M\-' notation, except for LF and TAB
+.TP
+\fB\-\-verbose\fR
+verbose mode (show error messages)
 .SH "REPORTING BUGS"
 Report bugs to zutils\-bug@nongnu.org
+.br
 Zutils home page: http://www.nongnu.org/zutils/zutils.html
 .SH COPYRIGHT
-Copyright \(co 2009 Antonio Diaz Diaz.
-This script is free software: you have unlimited permission
-to copy, distribute and modify it.
+Copyright \(co 2010 Antonio Diaz Diaz.
+License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
+.br
+This is free software: you are free to change and redistribute it.
+There is NO WARRANTY, to the extent permitted by law.
diff --git a/doc/zcmp.1 b/doc/zcmp.1
new file mode 100644
index 0000000..ab3da39
--- /dev/null
+++ b/doc/zcmp.1
@@ -0,0 +1,67 @@
+.\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.37.1.
+.TH ZCMP "1" "November 2010" "Zcmp (zutils) 0.8" "User Commands"
+.SH NAME
+Zcmp \- decompress and compare two files byte by byte
+.SH SYNOPSIS
+.B zcmp
+[\fIoptions\fR] \fIfile1 \fR[\fIfile2\fR]
+.SH DESCRIPTION
+Zcmp compares two files ("\-" means standard input), and if they
+differ, tells the first byte and line number where they differ. Bytes
+and lines are numbered starting with 1. If any given file is compressed,
+its uncompressed content is used. Compressed files are uncompressed on
+the fly; no temporary files are created.
+The supported compressors are bzip2, gzip, lzip and xz.
+.PP
+Compares <file1> to <file2>. If <file2> is omitted zcmp tries the
+following:
+If <file1> is compressed, compares <file1> to the file with the
+corresponding decompressed file name (removes the extension from
+<file1>).
+If <file1> is not compressed, compares <file1> to the uncompressed
+contents of <file1>.[bz2|gz|lz|xz] (the first one that is found).
+If no suitable file is found, compares <file1> to data read from
+standard input.
+.PP
+Exit status is 0 if inputs are identical, 1 if different, 2 if trouble.
+.SH OPTIONS
+.TP
+\fB\-h\fR, \fB\-\-help\fR
+display this help and exit
+.TP
+\fB\-V\fR, \fB\-\-version\fR
+output version information and exit
+.TP
+\fB\-b\fR, \fB\-\-print\-bytes\fR
+print differing bytes
+.TP
+\fB\-i\fR, \fB\-\-ignore\-initial=\fR<n>[,<n2>]
+ignore differences in the first <n> bytes
+.TP
+\fB\-l\fR, \fB\-\-list\fR
+list position, value of all differing bytes
+.TP
+\fB\-n\fR, \fB\-\-bytes=\fR<n>
+compare at most <n> bytes
+.TP
+\fB\-q\fR, \fB\-\-quiet\fR
+suppress all messages
+.TP
+\fB\-s\fR, \fB\-\-silent\fR
+(same as \fB\-\-quiet\fR)
+.TP
+\fB\-v\fR, \fB\-\-verbose\fR
+verbose mode (same as \fB\-\-list\fR)
+.PP
+Numbers may be followed by a multiplier: k = kB = 10^3 = 1000,
+Ki = KiB = 2^10 = 1024, M = 10^6, Mi = 2^20, G = 10^9, Gi = 2^30, etc...
+.SH "REPORTING BUGS"
+Report bugs to zutils\-bug@nongnu.org
+.br
+Zutils home page: http://www.nongnu.org/zutils/zutils.html
+.SH COPYRIGHT
+Copyright \(co 2010 Antonio Diaz Diaz.
+License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
+.br
+This is free software: you are free to change and redistribute it.
+There is NO WARRANTY, to the extent permitted by law.
diff --git a/doc/zdiff.1 b/doc/zdiff.1
index dc7abdb..f6417c2 100644
--- a/doc/zdiff.1
+++ b/doc/zdiff.1
@@ -1,27 +1,29 @@
-.\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.36.
-.TH ZDIFF "1" "December 2009" "Zdiff (zutils) 0.8-rc1" "User Commands"
+.\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.37.1.
+.TH ZDIFF "1" "November 2010" "Zdiff (zutils) 0.8" "User Commands"
 .SH NAME
-Zdiff \- compare compressed files
+Zdiff \- decompress and compare two files line by line
 .SH SYNOPSIS
 .B zdiff
-[\fIOPTIONS\fR] [\fIDIFF_OPTIONS\fR] \fIFILE1 \fR[\fIFILE2\fR]
+[\fIoptions\fR] \fIfile1 \fR[\fIfile2\fR]
 .SH DESCRIPTION
-Zdiff \- Diff/cmp wrapper for compressed files.
+Zdiff compares two files ("\-" means standard input), and if they
+differ, shows the differences line by line. If any given file is
+compressed, its uncompressed content is used. Zdiff is a front end to
+the diff program and has the limitation that messages from diff refer to
+temporary filenames instead of those specified.
+The supported compressors are bzip2, gzip, lzip and xz.
 .PP
-Zdiff is a wrapper script around the diff and cmp commands that allows
-transparent comparison of any combination of compressed and
-non\-compressed files. If any given file is compressed, its uncompressed
-content is used. The supported compressors are bzip2, gzip, lzip and xz.
+Compares <file1> to <file2>. If <file2> is omitted zdiff tries the
+following:
+If <file1> is compressed, compares <file1> to the file with the
+corresponding decompressed file name (removes the extension from
+<file1>).
+If <file1> is not compressed, compares <file1> to the uncompressed
+contents of <file1>.[bz2|gz|lz|xz] (the first one that is found).
+If no suitable file is found, compares <file1> to data read from
+standard input.
 .PP
-Zcmp is a shortcut for "zdiff \fB\-\-cmp\fR"
-.PP
-Compares FILE1 to FILE2. If FILE2 is omitted and FILE1 is compressed,
-compares FILE1 to the file with the corresponding decompressed file
-name (removes the extension from FILE1). If FILE2 is omitted and FILE1
-is not compressed, compares FILE1 to the uncompressed contents of
-FILE1.[bz2|gz|lz|xz] (the first one that is found).
-DIFF_OPTIONS are passed directly to diff or cmp.
-The exit status from diff or cmp is preserved.
+Exit status is 0 if inputs are identical, 1 if different, 2 if trouble.
 .SH OPTIONS
 .TP
 \fB\-h\fR, \fB\-\-help\fR
@@ -30,15 +32,63 @@ display this help and exit
 \fB\-V\fR, \fB\-\-version\fR
 output version information and exit
 .TP
-\fB\-\-diff\fR
-use diff to compare files (default)
+\fB\-a\fR, \fB\-\-text\fR
+treat all files as text
+.TP
+\fB\-b\fR, \fB\-\-ignore\-space\-change\fR
+ignore changes in the amount of white space
+.TP
+\fB\-B\fR, \fB\-\-ignore\-blank\-lines\fR
+ignore changes whose lines are all blank
+.TP
+\fB\-c\fR
+use the context output format
+.TP
+\fB\-C\fR, \fB\-\-context=\fR<n>
+same as \fB\-c\fR but use <n> lines of context
+.TP
+\fB\-d\fR, \fB\-\-minimal\fR
+try hard to find a smaller set of changes
+.TP
+\fB\-E\fR, \fB\-\-ignore\-tab\-expansion\fR
+ignore changes due to tab expansion
+.TP
+\fB\-i\fR, \fB\-\-ignore\-case\fR
+ignore case differences in file contents
 .TP
-\fB\-\-cmp\fR
-use cmp to compare files
+\fB\-p\fR, \fB\-\-show\-c\-function\fR
+show which C function each change is in
+.TP
+\fB\-q\fR, \fB\-\-brief\fR
+output only whether files differ
+.TP
+\fB\-s\fR, \fB\-\-report\-identical\-files\fR
+report when two files are identical
+.TP
+\fB\-t\fR, \fB\-\-expand\-tabs\fR
+expand tabs to spaces in output
+.TP
+\fB\-T\fR, \fB\-\-initial\-tab\fR
+make tabs line up by prepending a tab
+.TP
+\fB\-u\fR
+use the unified output format
+.TP
+\fB\-U\fR, \fB\-\-unified=\fR<n>
+same as \fB\-u\fR but use <n> lines of context
+.TP
+\fB\-w\fR, \fB\-\-ignore\-all\-space\fR
+ignore all white space
+.PP
+Numbers may be followed by a multiplier: k = kB = 10^3 = 1000,
+Ki = KiB = 2^10 = 1024, M = 10^6, Mi = 2^20, G = 10^9, Gi = 2^30, etc...
 .SH "REPORTING BUGS"
 Report bugs to zutils\-bug@nongnu.org
+.br
 Zutils home page: http://www.nongnu.org/zutils/zutils.html
 .SH COPYRIGHT
-Copyright \(co 2009 Antonio Diaz Diaz.
-This script is free software: you have unlimited permission
-to copy, distribute and modify it.
+Copyright \(co 2010 Antonio Diaz Diaz.
+License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
+.br
+This is free software: you are free to change and redistribute it.
+There is NO WARRANTY, to the extent permitted by law.
diff --git a/doc/zgrep.1 b/doc/zgrep.1
index fee5e3d..aab13b2 100644
--- a/doc/zgrep.1
+++ b/doc/zgrep.1
@@ -1,39 +1,115 @@
-.\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.36.
-.TH ZGREP "1" "December 2009" "Zgrep (zutils) 0.8-rc1" "User Commands"
+.\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.37.1.
+.TH ZGREP "1" "November 2010" "Zgrep (zutils) 0.8" "User Commands"
 .SH NAME
 Zgrep \- search compressed files for a regular expression
 .SH SYNOPSIS
 .B zgrep
-[\fIOPTIONS\fR] [\fIGREP_OPTIONS\fR] \fIPATTERN \fR[\fIFILES\fR]
+[\fIoptions\fR] \fI<pattern> \fR[\fIfiles\fR]
 .SH DESCRIPTION
-Zgrep \- Grep wrapper for compressed files.
-.PP
-Zgrep is a wrapper script around the grep command that allows
-transparent search on any combination of compressed and non\-compressed
-files. If any given file is compressed, its uncompressed content is
-used. If a given file does not exist, zgrep tries the compressed file
-names corresponding to the supported compressors. If no files are
-specified, data is read from standard input, decompressed if needed, and
-fed to grep. Data read from standard input must be of the same type; all
-uncompressed or all compressed with the same compressor.
+Zgrep is a front end to the grep program that allows transparent search
+on any combination of compressed and non\-compressed files. If any given
+file is compressed, its uncompressed content is used. If a given file
+does not exist, and its name does not end with one of the known
+extensions, zgrep tries the compressed file names corresponding to the
+supported compressors. If no files are specified, data is read from
+standard input, decompressed if needed, and fed to grep. Data read from
+standard input must be of the same type; all uncompressed or all
+compressed with the same compressor.
 The supported compressors are bzip2, gzip, lzip and xz.
 .PP
-Zegrep is a shortcut for "zgrep \fB\-E\fR"
-Zfgrep is a shortcut for "zgrep \fB\-F\fR"
-.PP
-GREP_OPTIONS are passed directly to grep.
-The exit status from grep is preserved.
+Exit status is 0 if match, 1 if no match, 2 if trouble.
 .SH OPTIONS
 .TP
-\fB\-h\fR, \fB\-\-help\fR
+\fB\-\-help\fR
 display this help and exit
 .TP
 \fB\-V\fR, \fB\-\-version\fR
 output version information and exit
+.TP
+\fB\-a\fR, \fB\-\-text\fR
+treat all files as text
+.TP
+\fB\-A\fR, \fB\-\-after\-context=\fR<n>
+print <n> lines of trailing context
+.TP
+\fB\-b\fR, \fB\-\-byte\-offset\fR
+print the byte offset of each line
+.TP
+\fB\-B\fR, \fB\-\-before\-context=\fR<n>
+print <n> lines of leading context
+.TP
+\fB\-c\fR, \fB\-\-count\fR
+only print a count of matching lines per file
+.TP
+\fB\-C\fR, \fB\-\-context=\fR<n>
+print <n> lines of output context
+.TP
+\fB\-e\fR, \fB\-\-regexp=\fR<pattern>
+use <pattern> as the pattern to match
+.TP
+\fB\-E\fR, \fB\-\-extended\-regexp\fR
+<pattern> is an extended regular expression
+.TP
+\fB\-f\fR, \fB\-\-file=\fR<file>
+obtain patterns from <file>
+.TP
+\fB\-F\fR, \fB\-\-fixed\-strings\fR
+<pattern> is a set of newline\-separated strings
+.TP
+\fB\-h\fR, \fB\-\-no\-filename\fR
+suppress the prefixing filename on output
+.TP
+\fB\-H\fR, \fB\-\-with\-filename\fR
+print the filename for each match
+.TP
+\fB\-i\fR, \fB\-\-ignore\-case\fR
+ignore case distinctions
+.TP
+\fB\-I\fR
+ignore binary files
+.TP
+\fB\-l\fR, \fB\-\-files\-with\-matches\fR
+only print names of files containing matches
+.TP
+\fB\-L\fR, \fB\-\-files\-without\-match\fR
+only print names of files containing no matches
+.TP
+\fB\-m\fR, \fB\-\-max\-count=\fR<n>
+stop after <n> matches
+.TP
+\fB\-n\fR, \fB\-\-line\-number\fR
+print the line number of each line
+.TP
+\fB\-o\fR, \fB\-\-only\-matching\fR
+show only the part of a line matching <pattern>
+.TP
+\fB\-q\fR, \fB\-\-quiet\fR
+suppress all messages
+.TP
+\fB\-r\fR, \fB\-\-recursive\fR
+operate recursively on directories
+.TP
+\fB\-s\fR, \fB\-\-no\-messages\fR
+suppress error messages
+.TP
+\fB\-v\fR, \fB\-\-invert\-match\fR
+select non\-matching lines
+.TP
+\fB\-\-verbose\fR
+verbose mode (show error messages)
+.TP
+\fB\-w\fR, \fB\-\-word\-regexp\fR
+match only whole words
+.TP
+\fB\-x\fR, \fB\-\-line\-regexp\fR
+match only whole lines
 .SH "REPORTING BUGS"
 Report bugs to zutils\-bug@nongnu.org
+.br
 Zutils home page: http://www.nongnu.org/zutils/zutils.html
 .SH COPYRIGHT
-Copyright \(co 2009 Antonio Diaz Diaz.
-This script is free software: you have unlimited permission
-to copy, distribute and modify it.
+Copyright \(co 2010 Antonio Diaz Diaz.
+License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
+.br
+This is free software: you are free to change and redistribute it.
+There is NO WARRANTY, to the extent permitted by law.
diff --git a/doc/ztest.1 b/doc/ztest.1
index 2c53401..9a36415 100644
--- a/doc/ztest.1
+++ b/doc/ztest.1
@@ -1,20 +1,18 @@
-.\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.36.
-.TH ZTEST "1" "December 2009" "Ztest (zutils) 0.8-rc1" "User Commands"
+.\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.37.1.
+.TH ZTEST "1" "November 2010" "Ztest (zutils) 0.8" "User Commands"
 .SH NAME
 Ztest \- verify integrity of compressed files
 .SH SYNOPSIS
 .B ztest
-[\fIOPTIONS\fR] [\fIFILES\fR]
+[\fIoptions\fR] [\fIfiles\fR]
 .SH DESCRIPTION
-Ztest \- Test integrity of compressed files.
-.PP
 Ztest verifies the integrity of the specified compressed files.
 Non\-compressed files are ignored. If no files are specified, the
 integrity of compressed data read from standard input is verified. Data
 read from standard input must be all compressed with the same compressor.
 The supported compressors are bzip2, gzip, lzip and xz.
 .PP
-The exit status is 1 if any compressed file is corrupt, 0 otherwise.
+Exit status is 2 if any compressed file is corrupt, 0 otherwise.
 .SH OPTIONS
 .TP
 \fB\-h\fR, \fB\-\-help\fR
@@ -33,8 +31,11 @@ operate recursively on directories
 be verbose (a 2nd \fB\-v\fR gives more)
 .SH "REPORTING BUGS"
 Report bugs to zutils\-bug@nongnu.org
+.br
 Zutils home page: http://www.nongnu.org/zutils/zutils.html
 .SH COPYRIGHT
-Copyright \(co 2009 Antonio Diaz Diaz.
-This script is free software: you have unlimited permission
-to copy, distribute and modify it.
+Copyright \(co 2010 Antonio Diaz Diaz.
+License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
+.br
+This is free software: you are free to change and redistribute it.
+There is NO WARRANTY, to the extent permitted by law.
diff --git a/doc/zutils.info b/doc/zutils.info
index e9762b9..b7f1250 100644
--- a/doc/zutils.info
+++ b/doc/zutils.info
diff --git a/doc/zutils.texinfo b/doc/zutils.texinfo
index 5442249..bb6eb6c 100644
--- a/doc/zutils.texinfo
+++ b/doc/zutils.texinfo
@@ -5,8 +5,8 @@
 @finalout
 @c %**end of header
 
-@set UPDATED 1 December 2009
-@set VERSION 0.8-rc1
+@set UPDATED 15 November 2010
+@set VERSION 0.8
 
 @dircategory Data Compression
 @direntry
@@ -24,7 +24,9 @@
 @vskip 0pt plus 1filll
 @end titlepage
 
+@ifnothtml
 @contents
+@end ifnothtml
 
 @node Top
 @top
@@ -32,17 +34,18 @@
 This manual is for Zutils (version @value{VERSION}, @value{UPDATED}).
 
 @menu
-* Introduction::	Purpose and features of zutils
-* Zcat::		Concatenating compressed files
-* Zcmp/Zdiff::		Comparing compressed files
-* Zgrep::		Searching inside compressed files
-* Ztest::		Testing integrity of compressed files
-* Problems::		Reporting bugs
-* Concept Index::	Index of concepts
+* Introduction::        Purpose and features of zutils
+* Zcat::                Concatenating compressed files
+* Zcmp::                Comparing compressed files byte by byte
+* Zdiff::               Comparing compressed files line by line
+* Zgrep::               Searching inside compressed files
+* Ztest::               Testing integrity of compressed files
+* Problems::            Reporting bugs
+* Concept Index::       Index of concepts
 @end menu
 
 @sp 1
-Copyright @copyright{} 2008, 2009 Antonio Diaz Diaz.
+Copyright @copyright{} 2008, 2009, 2010 Antonio Diaz Diaz.
 
 This manual is free documentation: you have unlimited permission
 to copy, distribute and modify it.
@@ -52,148 +55,443 @@ to copy, distribute and modify it.
 @chapter Introduction
 @cindex introduction
 
-Zutils is a collection of utilities for dealing with any combination of
-compressed and non-compressed files transparently. The supported
-compressors are bzip2, gzip, lzip and xz.
+Zutils is a collection of utilities able to deal with any combination of
+compressed and non-compressed files transparently. If any given file,
+including standard input, is compressed, its uncompressed content is
+used. Compressed files are decompressed on the fly; no temporary files
+are created. These utilities are not wrapper scripts but safer and more
+efficient C++ programs. In particular the @samp{--recursive} option is
+very efficient in those utilities supporting it.
 
-The currently provided utilities are zcat, zcmp, zdiff, zegrep, zfgrep,
-zgrep and ztest.
+@noindent
+The provided utilities are zcat, zcmp, zdiff, zgrep and ztest.@*
+The supported compressors are bzip2, gzip, lzip and xz.
+
+@sp 1
+Numbers given as arguments to options (positions, sizes) may be followed
+by a multiplier and an optional @samp{B} for "byte".
+
+Table of SI and binary prefixes (unit multipliers):
+
+@multitable {Prefix} {kilobyte  (10^3 = 1000)} {|} {Prefix} {kibibyte (2^10 = 1024)}
+@item Prefix @tab Value               @tab | @tab Prefix @tab Value
+@item k @tab kilobyte  (10^3 = 1000)  @tab | @tab Ki @tab kibibyte (2^10 = 1024)
+@item M @tab megabyte  (10^6)         @tab | @tab Mi @tab mebibyte (2^20)
+@item G @tab gigabyte  (10^9)         @tab | @tab Gi @tab gibibyte (2^30)
+@item T @tab terabyte  (10^12)        @tab | @tab Ti @tab tebibyte (2^40)
+@item P @tab petabyte  (10^15)        @tab | @tab Pi @tab pebibyte (2^50)
+@item E @tab exabyte   (10^18)        @tab | @tab Ei @tab exbibyte (2^60)
+@item Z @tab zettabyte (10^21)        @tab | @tab Zi @tab zebibyte (2^70)
+@item Y @tab yottabyte (10^24)        @tab | @tab Yi @tab yobibyte (2^80)
+@end multitable
 
 
 @node Zcat
 @chapter Zcat
 @cindex zcat
 
-Zcat is a wrapper script around the cat command that allows transparent
-concatenation of any combination of compressed and non-compressed files.
-If any given file is compressed, its uncompressed content is used. If a
-given file does not exist, zcat tries the compressed file names
+Zcat copies each given file (@samp{-} means standard input), to standard
+output. If any given file is compressed, its uncompressed content is
+used. If a given file does not exist, and its name does not end with one
+of the known extensions, zcat tries the compressed file names
 corresponding to the supported compressors. If no files are specified,
 data is read from standard input, decompressed if needed, and sent to
-stdout. Data read from standard input must be of the same type; all
-uncompressed or all compressed with the same compressor.
+standard output. Data read from standard input must be of the same type;
+all uncompressed or all compressed with the same compressor.
 
 The format for running zcat is:
 
 @example
-zcat [@var{options}] [@var{cat_options}] [@var{files}]
+zcat [@var{options}] [@var{files}]
 @end example
 
 @noindent
-@var{cat_options} are passed directly to cat. The exit status from cat
-is preserved.
+Exit status is 0 if no errors occurred, 1 otherwise.
 
 Zcat supports the following options:
 
 @table @samp
-@item --help
-@itemx -h
+@item -h
+@itemx --help
 Print an informative help message describing the options and exit.
 
-@item --version
-@itemx -V
+@item -V
+@itemx --version
 Print the version number of zcat on the standard output and exit.
 
-@item --recursive
-@itemx -r
+@item -A
+@itemx --show-all
+Equivalent to @samp{-vET}.
+
+@item -b
+@itemx --number-nonblank
+Number all nonblank output lines, starting with 1. The line count is
+unlimited.
+
+@item -e
+Equivalent to @samp{-vE}.
+
+@item -E
+@itemx --show-ends
+Print a @samp{$} after the end of each line.
+
+@item -n
+@itemx --number
+Number all output lines, starting with 1. The line count is unlimited.
+
+@item -q
+@itemx --quiet
+Quiet operation. Suppress all messages.
+
+@item -r
+@itemx --recursive
 Operate recursively on directories.
 
+@item -s
+@itemx --squeeze-blank
+Replace multiple adjacent blank lines with a single blank line.
+
+@item -t
+Equivalent to @samp{-vT}.
+
+@item -T
+@itemx --show-tabs
+Print TAB characters as @samp{^I}.
+
+@item -v
+@itemx --show-nonprinting
+Print control characters except for LF (newline) and TAB using @samp{^}
+notation and precede characters larger than 127 with @samp{M-} (which
+stands for "meta").
+
+@item --verbose
+Verbose mode. Show error messages.
+
 @end table
 
 
-@node Zcmp/Zdiff
-@chapter Zcmp/Zdiff
+@node Zcmp
+@chapter Zcmp
 @cindex zcmp
-@cindex zdiff
 
-Zdiff is a wrapper script around the diff and cmp commands that allows
-transparent comparison of any combination of compressed and
-non-compressed files. If any given file is compressed, its uncompressed
-content is used.
+Zcmp compares two files (@samp{-} means standard input), and if they
+differ, tells the first byte and line number where they differ. Bytes
+and lines are numbered starting with 1. If any given file is compressed,
+its uncompressed content is used. Compressed files are decompressed on
+the fly; no temporary files are created.
+
+The format for running zcmp is:
+
+@example
+zcmp [@var{options}] @var{file1} [@var{file2}]
+@end example
+
+@noindent
+Compares @var{file1} to @var{file2}. If @var{file2} is omitted zcmp
+tries the following:@*
+If @var{file1} is compressed, compares @var{file1} to the file with the
+corresponding decompressed file name (removes the extension from
+@var{file1}).@*
+If @var{file1} is not compressed, compares @var{file1} to the
+uncompressed contents of @var{file1}.[bz2|gz|lz|xz] (the first one that
+is found).@*
+If no suitable file is found, compares @var{file1} to data read from
+standard input.
 
 @noindent
-Zcmp is a shortcut for @samp{zdiff --cmp}
+An exit status of 0 means no differences were found, 1 means some
+differences were found, and 2 means trouble.
+
+Zcmp supports the following options:
+
+@table @samp
+@item -h
+@itemx --help
+Print an informative help message describing the options and exit.
+
+@item -V
+@itemx --version
+Print the version number of zcmp on the standard output and exit.
+
+@item -b
+@itemx --print-bytes
+Print the differing bytes. Print control bytes as a @samp{^} followed by
+a letter, and precede bytes larger than 127 with @samp{M-} (which stands
+for "meta").
+
+@item -i @var{size}
+@itemx --ignore-initial=@var{size}
+Ignore any differences in the first @var{size} bytes of the input files.
+Treat files with fewer than @var{size} bytes as if they were empty. If
+@var{size} is in the form @samp{@var{size1},@var{size2}}, ignore the
+first @var{size1} bytes of the first input file and the first
+@var{size2} bytes of the second input file.
+
+@item -l
+@itemx -v
+@itemx --list
+@itemx --verbose
+Print the byte numbers (in decimal) and values (in octal) of all
+differing bytes.
+
+@item -n @var{count}
+@itemx --bytes=@var{count}
+Compare at most @var{count} input bytes.
+
+@item -q
+@itemx -s
+@itemx --quiet
+@itemx --silent
+Do not print anything; only return an exit status indicating whether the
+files differ.
+
+@end table
+
+
+@node Zdiff
+@chapter Zdiff
+@cindex zdiff
+
+Zdiff compares two files (@samp{-} means standard input), and if they
+differ, shows the differences line by line. If any given file is
+compressed, its uncompressed content is used. Zdiff is a front end to
+the diff program and has the limitation that messages from diff refer to
+temporary filenames instead of those specified.
 
 The format for running zdiff is:
 
 @example
-zdiff [@var{options}] [@var{diff_options}] @var{file1} [@var{file2}]
+zdiff [@var{options}] @var{file1} [@var{file2}]
 @end example
 
 @noindent
-Compares @var{file1} to @var{file2}. If @var{file2} is omitted and
-@var{file1} is compressed, compares @var{file1} to the file with the
+Compares @var{file1} to @var{file2}. If @var{file2} is omitted zdiff
+tries the following:@*
+If @var{file1} is compressed, compares @var{file1} to the file with the
 corresponding decompressed file name (removes the extension from
-@var{file1}). If @var{file2} is omitted and @var{file1} is not
-compressed, compares @var{file1} to the uncompressed contents of
-@var{file1}.[bz2|gz|lz|xz] (the first one that is found).
-@var{diff_options} are passed directly to diff or cmp. The exit status
-from diff or cmp is preserved.
+@var{file1}).@*
+If @var{file1} is not compressed, compares @var{file1} to the
+uncompressed contents of @var{file1}.[bz2|gz|lz|xz] (the first one that
+is found).@*
+If no suitable file is found, compares @var{file1} to data read from
+standard input.
+
+@noindent
+An exit status of 0 means no differences were found, 1 means some
+differences were found, and 2 means trouble.
 
 Zdiff supports the following options:
 
 @table @samp
-@item --help
-@itemx -h
+@item -h
+@itemx --help
 Print an informative help message describing the options and exit.
 
-@item --version
-@itemx -V
+@item -V
+@itemx --version
 Print the version number of zdiff on the standard output and exit.
 
-@item --diff
-Use diff to compare files (default).
+@item -a
+@itemx --text
+Treat all files as text.
 
-@item --cmp
-Use cmp to compare files.
+@item -b
+@itemx --ignore-space-change
+Ignore changes in the amount of white space.
 
-@end table
+@item -B
+@itemx --ignore-blank-lines
+Ignore changes whose lines are all blank.
+
+@itemx -c
+Use the context output format.
+
+@item -C @var{n}
+@itemx --context=@var{n}
+Same as -c but use @var{n} lines of context.
+
+@item -d
+@itemx --minimal
+Try hard to find a smaller set of changes.
 
-Zdiff has the limitation that messages from the diff or cmp programs
-refer to temporary filenames instead of those specified.
+@item -E
+@itemx --ignore-tab-expansion
+Ignore changes due to tab expansion.
+
+@item -i
+@itemx --ignore-case
+Ignore case differences in file contents.
+
+@item -p
+@itemx --show-c-function
+Show which C function each change is in.
+
+@item -q
+@itemx --brief
+Output only whether files differ.
+
+@item -s
+@itemx --report-identical-files
+Report when two files are identical.
+
+@item -t
+@itemx --expand-tabs
+Expand tabs to spaces in output.
+
+@item -T
+@itemx --initial-tab
+Make tabs line up by prepending a tab.
+
+@item -u
+Use the unified output format.
+
+@item -U @var{n}
+@itemx --unified=@var{n}
+Same as -u but use @var{n} lines of context.
+
+@item -w
+@itemx --ignore-all-space
+Ignore all white space.
+
+@end table
 
 
 @node Zgrep
 @chapter Zgrep
-@cindex zegrep
-@cindex zfgrep
 @cindex zgrep
 
-Zgrep is a wrapper script around the grep command that allows
-transparent search on any combination of compressed and non-compressed
-files. If any given file is compressed, its uncompressed content is
-used. If a given file does not exist, zgrep tries the compressed file
-names corresponding to the supported compressors. If no files are
-specified, data is read from standard input, decompressed if needed, and
-fed to grep. Data read from standard input must be of the same type; all
-uncompressed or all compressed with the same compressor.
-
-@noindent
-Zegrep is a shortcut for @samp{zgrep -E}@*
-Zfgrep is a shortcut for @samp{zgrep -F}
-
+Zgrep is a front end to the grep program that allows transparent search
+on any combination of compressed and non-compressed files. If any given
+file is compressed, its uncompressed content is used. If a given file
+does not exist, and its name does not end with one of the known
+extensions, zgrep tries the compressed file names corresponding to the
+supported compressors. If no files are specified, data is read from
+standard input, decompressed if needed, and fed to grep. Data read from
+standard input must be of the same type; all uncompressed or all
+compressed with the same compressor.
 
 The format for running zgrep is:
 
 @example
-zgrep [@var{options}] [@var{grep_options}] @var{pattern} [@var{files}]
+zgrep [@var{options}] @var{pattern} [@var{files}]
 @end example
 
 @noindent
-@var{grep_options} are passed directly to grep. The exit status from
-grep is preserved.
+An exit status of 0 means at least one match was found, 1 means no
+matches were found, and 2 means trouble.
 
 Zgrep supports the following options:
 
 @table @samp
 @item --help
-@itemx -h
 Print an informative help message describing the options and exit.
 
-@item --version
-@itemx -V
+@item -V
+@itemx --version
 Print the version number of zgrep on the standard output and exit.
 
+@item -a
+@itemx --text
+Treat all files as text.
+
+@item -A @var{n}
+@itemx --after-context=@var{n}
+Print @var{n} lines of trailing context.
+
+@item -b
+@itemx --byte-offset
+Print the byte offset of each line.
+
+@item -B @var{n}
+@itemx --before-context=@var{n}
+Print @var{n} lines of leading context.
+
+@item -c
+@itemx --count
+Only print a count of matching lines per file.
+
+@item -C @var{n}
+@itemx --context=@var{n}
+Print @var{n} lines of output context.
+
+@item -e @var{pattern}
+@itemx --regexp=@var{pattern}
+Use @var{pattern} as the pattern to match.
+
+@item -E
+@itemx --extended-regexp
+Treat @var{pattern} as an extended regular expression.
+
+@item -f @var{file}
+@itemx --file=@var{file}
+Obtain patterns from @var{file}, one per line.
+
+@item -F
+@itemx --fixed-strings
+Treat @var{pattern} as a set of newline-separated strings.
+
+@item -h
+@itemx --no-filename
+Suppress the prefixing filename on output.
+
+@item -H
+@itemx --with-filename
+Print the filename for each match.
+
+@item -i
+@itemx --ignore-case
+Ignore case distinctions.
+
+@item -I
+Ignore binary files.
+
+@item -l
+@itemx --files-with-matches
+Only print names of files containing at least one match.
+
+@item -L
+@itemx --files-without-match
+Only print names of files not containing any matches.
+
+@item -m @var{n}
+@itemx --max-count=@var{n}
+Stop after @var{n} matches.
+
+@item -n
+@itemx --line-number
+Prefix each matched line with its line number in the input file.
+
+@item -o
+@itemx --only-matching
+Show only the part of matching lines that actually matches @var{pattern}.
+
+@item -q
+@itemx --quiet
+Suppress all messages.
+
+@item -r
+@itemx --recursive
+Operate recursively on directories.
+
+@item -s
+@itemx --no-messages
+Suppress error messages.
+
+@item -v
+@itemx --invert-match
+Select non-matching lines.
+
+@item --verbose
+Verbose mode. Show error messages.
+
+@item -w
+@itemx --word-regexp
+Match only whole words.
+
+@item -x
+@itemx --line-regexp
+Match only whole lines.
+
 @end table
 
 
@@ -213,29 +511,31 @@ ztest [@var{options}] [@var{files}]
 @end example
 
 @noindent
-The exit status is 0 if all files verify OK, 1 otherwise.
+The exit status is 0 if all files verify OK, 1 for environmental
+problems (file not found, invalid flags, I/O errors, etc), 2 to indicate
+a corrupt or invalid input file.
 
 Ztest supports the following options:
 
 @table @samp
-@item --help
-@itemx -h
+@item -h
+@itemx --help
 Print an informative help message describing the options and exit.
 
-@item --version
-@itemx -V
+@item -V
+@itemx --version
 Print the version number of ztest on the standard output and exit.
 
-@item --quiet
-@itemx -q
+@item -q
+@itemx --quiet
 Quiet operation. Suppress all messages.
 
-@item --recursive
-@itemx -r
+@item -r
+@itemx --recursive
 Operate recursively on directories.
 
-@item --verbose
-@itemx -v
+@item -v
+@itemx --verbose
 Verbose mode. Show the verify status for each file processed.
 Further -v's increase the verbosity level.
 
@@ -254,7 +554,7 @@ for all eternity, if not longer.
 
 If you find a bug in zutils, please send electronic mail to
 @email{zutils-bug@@nongnu.org}. Include the version number, which you can
-find by running @w{@samp{zdiff --version}}.
+find by running @w{@samp{zutils --version}}.
 
 
 @node Concept Index
diff --git a/main.cc b/main.cc
index eba364b..bc7c5fb 100644
--- a/main.cc
+++ b/main.cc
@@ -1,5 +1,5 @@
-/*  Zutils - A file format detector for compressed files
-    Copyright (C) 2009 Antonio Diaz Diaz.
+/*  Zutils - Utilities dealing with compressed files
+    Copyright (C) 2009, 2010 Antonio Diaz Diaz.
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -14,257 +14,69 @@
     You should have received a copy of the GNU General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
-/*
-    Return values: 0 for a normal exit, 1 for environmental problems
-    (file not found, invalid flags, I/O errors, etc), 2 to indicate a
-    corrupt or invalid input file, 3 for an internal consistency error
-    (eg, bug) which caused zutils to panic.
-*/
 
 #define _FILE_OFFSET_BITS 64
 
-#include <algorithm>
 #include <cerrno>
 #include <climits>
 #include <csignal>
 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
+#include <list>
 #include <string>
 #include <vector>
+#include <dirent.h>
 #include <fcntl.h>
 #include <stdint.h>
 #include <unistd.h>
-#include <utime.h>
 #include <sys/stat.h>
-#include <sys/time.h>
+#if defined(__MSVCRT__) || defined(__OS2__)
+#include <io.h>
+#endif
 
 #include "arg_parser.h"
+#include "zutils.h"
 
-#ifndef LLONG_MAX
-#define LLONG_MAX  0x7FFFFFFFFFFFFFFFLL
-#endif
-#ifndef LLONG_MIN
-#define LLONG_MIN  (-LLONG_MAX - 1LL)
-#endif
-#ifndef ULLONG_MAX
-#define ULLONG_MAX 0xFFFFFFFFFFFFFFFFULL
+#if CHAR_BIT != 8
+#error "Environments where CHAR_BIT != 8 are not supported."
 #endif
 
 
 namespace {
 
-const char * invocation_name = 0;
-const char * const Program_name    = "Zutils";
-const char * const program_name    = "zutils";
-const char * const program_year    = "2009";
-
-struct { const char * from; const char * to; } const known_extensions[] = {
-  { ".zf",  ""     },
-  { 0,      0      } };
-
-enum Mode { m_compress = 0, m_decompress, m_test };
-
-std::string output_filename;
-int outhandle = -1;
-int verbosity = 0;
-bool delete_output_on_interrupt = false;
-
-
-class Pretty_print
-  {
-  const char * const stdin_name;
-  const unsigned int stdin_name_len;
-  unsigned int longest_name;
-  std::string name_;
-  mutable bool first_post;
-
-public:
-  Pretty_print( const std::vector< std::string > & filenames )
-    : stdin_name( "(stdin)" ), stdin_name_len( std::strlen( stdin_name ) ),
-      longest_name( 0 ), first_post( false )
-    {
-    for( unsigned int i = 0; i < filenames.size(); ++i )
-      {
-      const std::string & s = filenames[i];
-      const unsigned int len = ( ( s == "-" ) ? stdin_name_len : s.size() );
-      if( len > longest_name ) longest_name = len;
-      }
-    if( longest_name == 0 ) longest_name = stdin_name_len;
-    }
-
-  void set_name( const std::string & filename )
-    {
-    if( filename.size() && filename != "-" ) name_ = filename;
-    else name_ = stdin_name;
-    first_post = true;
-    }
-
-  void reset() const throw() { if( name_.size() ) first_post = true; }
-  const char * name() const throw() { return name_.c_str(); }
-  void operator()( const char * const msg = 0 ) const throw();
-  };
-
+#ifdef O_BINARY
+const int o_binary = O_BINARY;
+#else
+const int o_binary = 0;
+#endif
 
-void Pretty_print::operator()( const char * const msg ) const throw()
-  {
-  if( verbosity >= 0 )
-    {
-    if( first_post )
-      {
-      first_post = false;
-      std::fprintf( stderr, "  %s: ", name_.c_str() );
-      for( unsigned int i = 0; i < longest_name - name_.size(); ++i )
-        std::fprintf( stderr, " " );
-      if( !msg ) std::fflush( stderr );
-      }
-    if( msg ) std::fprintf( stderr, "%s.\n", msg );
-    }
-  }
+enum Mode { m_none, m_zcat, m_zgrep, m_ztest };
 
 
 void show_help() throw()
   {
-  std::printf( "%s - A file format detector for compressed files.\n", Program_name );
-  std::printf( "\nUsage: %s [options] [files]\n", invocation_name );
-  std::printf( "\nOptions:\n" );
+  std::printf( "Zutils is a collection of utilities able to deal with any combination of\n" );
+  std::printf( "compressed and non-compressed files transparently. If any given file,\n" );
+  std::printf( "including standard input, is compressed, its uncompressed content is used.\n" );
+  std::printf( "The supported compressors are bzip2, gzip, lzip and xz.\n" );
+  std::printf( "\nUsage: %s <operation> [options] [files]\n", invocation_name );
+  std::printf( "\nTry `%s <operation> --help' for more specific help.\n", invocation_name );
+  std::printf( "\nOperations:\n" );
   std::printf( "  -h, --help                 display this help and exit\n" );
   std::printf( "  -V, --version              output version information and exit\n" );
-//  std::printf( "  -c, --stdout               send output to standard output\n" );
-//  std::printf( "  -d, --decompress           decompress\n" );
-//  std::printf( "  -f, --force                overwrite existing output files\n" );
-//  std::printf( "  -k, --keep                 keep (don't delete) input files\n" );
-  std::printf( "  -m, --magic=<type>         output magic bytes for given file type\n" );
-//  std::printf( "  -o, --output=<file>        if reading stdin, place the output into <file>\n" );
-  std::printf( "  -q, --quiet                suppress all messages\n" );
-  std::printf( "  -t, --test                 test compressed file type\n" );
-  std::printf( "  -v, --verbose              be verbose (a 2nd -v gives more)\n" );
-  std::printf( "\nReport bugs to zutils-bug@nongnu.org\n" );
-  std::printf( "Zutils home page: http://www.nongnu.org/zutils/zutils.html\n" );
+  std::printf( "      --zcat                 zcat operation\n" );
+  std::printf( "      --zgrep                zgrep operation\n" );
+  std::printf( "      --ztest                ztest operation\n" );
+  show_help_addr();
   }
 
 
-void show_version() throw()
+int simple_extension_index( const std::string & name ) throw()
   {
-  std::printf( "%s %s\n", Program_name, PROGVERSION );
-  std::printf( "Copyright (C) %s Antonio Diaz Diaz.\n", program_year );
-  std::printf( "License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>\n" );
-  std::printf( "This is free software: you are free to change and redistribute it.\n" );
-  std::printf( "There is NO WARRANTY, to the extent permitted by law.\n" );
-  }
-
-
-void show_error( const char * msg, const int errcode = 0, const bool help = false ) throw()
-  {
-  if( verbosity >= 0 )
+  for( int i = 0; simple_extensions[i]; ++i )
     {
-    if( msg && msg[0] != 0 )
-      {
-      std::fprintf( stderr, "%s: %s", program_name, msg );
-      if( errcode > 0 ) std::fprintf( stderr, ": %s", std::strerror( errcode ) );
-      std::fprintf( stderr, "\n" );
-      }
-    if( help && invocation_name && invocation_name[0] != 0 )
-      std::fprintf( stderr, "Try `%s --help' for more information.\n", invocation_name );
-    }
-  }
-
-
-void internal_error( const char * msg )
-  {
-  std::string s( "internal error: " ); s += msg;
-  show_error( s.c_str() );
-  std::exit( 3 );
-  }
-
-
-const char * format_num( long long num, long long limit = 9999,
-                         const int set_prefix = 0 ) throw()
-  {
-  const char * const si_prefix[8] =
-    { "k", "M", "G", "T", "P", "E", "Z", "Y" };
-  const char * const binary_prefix[8] =
-    { "Ki", "Mi", "Gi", "Ti", "Pi", "Ei", "Zi", "Yi" };
-  static bool si = false;
-  static char buf[16];
-
-  if( set_prefix ) si = ( set_prefix > 0 );
-  const int factor = ( si ) ? 1000 : 1024;
-  const char * const *prefix = ( si ) ? si_prefix : binary_prefix;
-  const char *p = "";
-  limit = std::max( 999LL, std::min( 999999LL, limit ) );
-
-  for( int i = 0; i < 8 && ( llabs( num ) > limit ||
-       ( llabs( num ) >= factor && num % factor == 0 ) ); ++i )
-    { num /= factor; p = prefix[i]; }
-  snprintf( buf, sizeof buf, "%lld %s", num, p );
-  return buf;
-  }
-
-
-long long getnum( const char * ptr, const int bs,
-                  const long long llimit = LLONG_MIN + 1,
-                  const long long ulimit = LLONG_MAX ) throw()
-  {
-  errno = 0;
-  char *tail;
-  long long result = strtoll( ptr, &tail, 0 );
-  if( tail == ptr )
-    {
-    show_error( "bad or missing numerical argument", 0, true );
-    std::exit( 1 );
-    }
-
-  if( !errno && tail[0] )
-    {
-    int factor = ( tail[1] == 'i' ) ? 1024 : 1000;
-    int exponent = 0;
-    bool bad_multiplier = false;
-    switch( tail[0] )
-      {
-      case ' ': break;
-      case 'b': if( bs > 0 ) { factor = bs; exponent = 1; }
-                else bad_multiplier = true;
-                break;
-      case 'Y': exponent = 8; break;
-      case 'Z': exponent = 7; break;
-      case 'E': exponent = 6; break;
-      case 'P': exponent = 5; break;
-      case 'T': exponent = 4; break;
-      case 'G': exponent = 3; break;
-      case 'M': exponent = 2; break;
-      case 'K': if( factor == 1024 ) exponent = 1; else bad_multiplier = true;
-                break;
-      case 'k': if( factor == 1000 ) exponent = 1; else bad_multiplier = true;
-                break;
-      default: bad_multiplier = true;
-      }
-    if( bad_multiplier )
-      {
-      show_error( "bad multiplier in numerical argument", 0, true );
-      std::exit( 1 );
-      }
-    for( int i = 0; i < exponent; ++i )
-      {
-      if( LLONG_MAX / factor >= llabs( result ) ) result *= factor;
-      else { errno = ERANGE; break; }
-      }
-    }
-  if( !errno && ( result < llimit || result > ulimit ) ) errno = ERANGE;
-  if( errno )
-    {
-    show_error( "numerical argument out of limits" );
-    std::exit( 1 );
-    }
-  return result;
-  }
-
-
-int extension_index( const std::string & name ) throw()
-  {
-  for( int i = 0; known_extensions[i].from; ++i )
-    {
-    const std::string ext( known_extensions[i].from );
+    const std::string ext( simple_extensions[i] );
     if( name.size() > ext.size() &&
         name.compare( name.size() - ext.size(), ext.size(), ext ) == 0 )
       return i;
@@ -273,449 +85,262 @@ int extension_index( const std::string & name ) throw()
   }
 
 
-int open_instream( const std::string & name, struct stat * in_statsp,
-                   const Mode program_mode, const int eindex,
-                   const bool force, const bool to_stdout ) throw()
+int open_instream( std::string & input_filename, const Mode program_mode ) throw()
   {
-  int inhandle = -1;
-  if( program_mode == m_compress && !force && eindex >= 0 )
-    {
-    if( verbosity >= 0 )
-      std::fprintf( stderr, "%s: input file `%s' already has `%s' suffix.\n",
-                    program_name, name.c_str(),
-                    known_extensions[eindex].from );
-    }
-  else
+  int infd = open( input_filename.c_str(), O_RDONLY | o_binary );
+  if( infd < 0 )
     {
-    inhandle = open( name.c_str(), O_RDONLY );
-    if( inhandle < 0 )
+    if( ( program_mode == m_zcat || program_mode == m_zgrep )
+        && simple_extension_index( input_filename ) < 0 )
       {
-      if( verbosity >= 0 )
-        std::fprintf( stderr, "%s: Can't open input file `%s': %s.\n",
-                      program_name, name.c_str(), std::strerror( errno ) );
-      }
-    else
-      {
-      const int i = fstat( inhandle, in_statsp );
-      const mode_t & mode = in_statsp->st_mode;
-      if( i < 0 || !( S_ISREG( mode ) || ( to_stdout &&
-                      ( S_ISFIFO( mode ) || S_ISSOCK( mode ) ||
-                        S_ISBLK( mode ) || S_ISCHR( mode ) ) ) ) )
+      for( int i = 0; simple_extensions[i]; ++i )
         {
-        if( verbosity >= 0 )
-          std::fprintf( stderr, "%s: input file `%s' is not a regular file%s.\n",
-                        program_name, name.c_str(),
-                        to_stdout ? "" : " and `--stdout' was not specified" );
-        close( inhandle );
-        inhandle = -1;
+        const std::string name( input_filename + simple_extensions[i] );
+        infd = open( name.c_str(), O_RDONLY | o_binary );
+        if( infd >= 0 ) { input_filename = name; break; }
         }
       }
+    if( infd < 0 && verbosity >= 0 )
+      std::fprintf( stderr, "%s: Can't open input file `%s': %s.\n",
+                    util_name, input_filename.c_str(), std::strerror( errno ) );
     }
-  return inhandle;
-  }
-
-
-void set_c_outname( const std::string & name ) throw()
-  {
-  output_filename = name;
-  output_filename += known_extensions[0].from;
-  }
-
-
-void set_d_outname( const std::string & name, const int i ) throw()
-  {
-  if( i >= 0 )
-    {
-    const std::string from( known_extensions[i].from );
-    if( name.size() > from.size() )
-      {
-      output_filename.assign( name, 0, name.size() - from.size() );
-      output_filename += known_extensions[i].to;
-      return;
-      }
-    }
-  output_filename = name; output_filename += ".out";
-  if( verbosity >= 0 )
-    std::fprintf( stderr, "%s: can't guess original name for `%s' -- using `%s'.\n",
-                  program_name, name.c_str(), output_filename.c_str() );
-  }
-
-
-bool open_outstream( const bool /*force*/ ) throw()
-  {
-/*  if( force )
-    outhandle = open( output_filename.c_str(), O_CREAT | O_TRUNC | O_WRONLY,
-                      S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH );
-  else outhandle = open( output_filename.c_str(), O_CREAT | O_EXCL | O_WRONLY,
-                         S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH );
-  if( outhandle < 0 )
-    {
-    if( errno == EEXIST ) outhandle = -2; else outhandle = -1;
-    if( verbosity >= 0 )
-      {
-      if( outhandle == -2 )
-        std::fprintf( stderr, "%s: Output file %s already exists, skipping.\n",
-                      program_name, output_filename.c_str() );
-      else
-        std::fprintf( stderr, "%s: Can't create output file `%s': %s.\n",
-                      program_name, output_filename.c_str(), std::strerror( errno ) );
-      }
-    }*/
-  return ( outhandle >= 0 );
-  }
-
-
-bool check_tty( const int inhandle, const Mode program_mode ) throw()
-  {
-  if( program_mode == m_compress && isatty( outhandle ) )
-    {
-    show_error( "I won't write compressed data to a terminal.", 0, true );
-    return false;
-    }
-  if( ( program_mode == m_decompress || program_mode == m_test ) &&
-      isatty( inhandle ) )
-    {
-    show_error( "I won't read compressed data from a terminal.", 0, true );
-    return false;
-    }
-  return true;
+  return infd;
   }
 
+#include "zcat.cc"
+#include "zgrep.cc"
+#include "ztest.cc"
 
-void cleanup_and_fail( const int retval ) throw()
-  {
-  if( delete_output_on_interrupt )
-    {
-    if( verbosity >= 0 )
-      std::fprintf( stderr, "%s: Deleting output file `%s', if it exists.\n",
-               program_name, output_filename.c_str() );
-    if( outhandle >= 0 ) { close( outhandle ); outhandle = -1; }
-    if( std::remove( output_filename.c_str() ) != 0 )
-      show_error( "WARNING: deletion of output file (apparently) failed." );
-    }
-  std::exit( retval );
-  }
-
-
-     // Set permissions, owner and times.
-void close_and_set_permissions( const struct stat * in_statsp, int * retvalp )
-  {
-  int tmp = 0;
-  if( in_statsp )
-    {
-    if( fchmod( outhandle, in_statsp->st_mode ) != 0 ) tmp = 1;
-    if( !tmp ) (void)fchown( outhandle, in_statsp->st_uid, in_statsp->st_gid );
-    // fchown will in many cases return with EPERM, which can be safely ignored.
-    }
-  if( close( outhandle ) == 0 ) outhandle = -1;
-  else cleanup_and_fail( 1 );
-  delete_output_on_interrupt = false;
-  if( !in_statsp ) return;
-  if( !tmp )
-    {
-    struct utimbuf t;
-    t.actime = in_statsp->st_atime;
-    t.modtime = in_statsp->st_mtime;
-    tmp = utime( output_filename.c_str(), &t );
-    }
-  if( tmp )
-    {
-    if( tmp > *retvalp ) *retvalp = tmp;
-    show_error( "I can't change output file attributes." );
-    cleanup_and_fail( *retvalp );
-    }
-  }
+} // end namespace
 
 
-// Returns the number of bytes really read.
-// If (returned value < size) and (errno == 0), means EOF was reached.
-//
-int readblock( const int fd, char * buf, const int size ) throw()
+int main( const int argc, const char * const argv[] )
   {
-  int rest = size;
-  errno = 0;
-  while( rest > 0 )
-    {
-    errno = 0;
-    const int n = read( fd, buf + size - rest, rest );
-    if( n > 0 ) rest -= n;
-    else if( n == 0 ) break;
-    else if( errno != EINTR && errno != EAGAIN ) break;
-    }
-  return ( rest > 0 ) ? size - rest : size;
-  }
-
+  enum { help_opt = 256, verbose_opt, zcat_opt, zgrep_opt, ztest_opt };
+  const Arg_parser::Option * options = 0;
+  int infd = -1;
+  Mode program_mode = m_none;
+  bool recursive = false;
+  std::string input_filename;
+  std::list< std::string > filenames;
+  Cat_options cat_options;
+  std::vector< const char * > grep_args;	// args to grep, maybe empty
+  std::vector< const char * > ztest_args;	// args to ztest, maybe empty
+  invocation_name = argv[0];
 
-// Returns the number of bytes really written.
-// If (returned value < size), it is always an error.
-//
-int writeblock( const int fd, const char * buf, const int size ) throw()
-  {
-  int rest = size;
-  errno = 0;
-  while( rest > 0 )
+  const Arg_parser::Option m_zcat_options[] =
     {
-    errno = 0;
-    const int n = write( fd, buf + size - rest, rest );
-    if( n > 0 ) rest -= n;
-    else if( errno && errno != EINTR && errno != EAGAIN ) break;
-    }
-  return ( rest > 0 ) ? size - rest : size;
-  }
-
-/*
-int compress( const int inhandle, const Pretty_print & pp,
-              const struct stat * in_statsp, int * retvalp )
-  {
-  long long in_size = 0, out_size = 0;
-  if( verbosity >= 1 )
+    { 'A', "show-all",         Arg_parser::no  },	// cat
+    { 'b', "number-nonblank",  Arg_parser::no  },	// cat
+    { 'c', "stdout",           Arg_parser::no  },	// gzip
+    { 'd', "decompress",       Arg_parser::no  },	// gzip
+    { 'e',  0,                 Arg_parser::no  },	// cat
+    { 'E', "show-ends",        Arg_parser::no  },	// cat
+    { 'f', "force",            Arg_parser::no  },	// gzip
+    { 'h', "help",             Arg_parser::no  },
+    { 'l', "list",             Arg_parser::no  },	// gzip
+    { 'L', "license",          Arg_parser::no  },	// gzip
+    { 'n', "number",           Arg_parser::no  },	// cat
+    { 'q', "quiet",            Arg_parser::no  },
+    { 'r', "recursive",        Arg_parser::no  },
+    { 's', "squeeze-blank",    Arg_parser::no  },	// cat
+    { 't',  0,                 Arg_parser::no  },	// cat
+    { 'T', "show-tabs",        Arg_parser::no  },	// cat
+    { 'v', "show-nonprinting", Arg_parser::no  },	// cat
+    { 'V', "version",          Arg_parser::no  },
+    { verbose_opt, "verbose",  Arg_parser::no  },
+    { zcat_opt,    "zcat",     Arg_parser::no  },
+    {  0 ,  0,                 Arg_parser::no  } };
+
+  const Arg_parser::Option m_zgrep_options[] =
     {
-    pp();
-    if( in_size <= 0 || out_size <= 0 )
-      std::fprintf( stderr, "no data compressed.\n" );
-    else
-      std::fprintf( stderr, "%6.3f:1, %6.3f bits/byte, "
-                            "%5.2f%% saved, %lld in, %lld out.\n",
-                    (double)in_size / out_size,
-                    ( 8.0 * out_size ) / in_size,
-                    100.0 * ( 1.0 - ( (double)out_size / in_size ) ),
-                    in_size, out_size );
-    }
-  return 0;
-  }
-
-
-int decompress( const int inhandle, const Pretty_print & pp )
-  {
-  if( verbosity >= 1 )
-    std::fprintf( stderr, "done\n" );
-  return 0;
-  }
-*/
-
-unsigned char xdigit( const int value ) throw()
-  {
-  if( value >= 0 && value <= 9 ) return '0' + value;
-  if( value >= 10 && value <= 15 ) return 'A' + value - 10;
-  return 0;
-  }
-
-
-int xtoi( const unsigned char ch ) throw()
-  {
-  switch( ch )
+    { 'a', "text",                  Arg_parser::no  },	// grep GNU
+    { 'A', "after-context",         Arg_parser::yes },	// grep GNU
+    { 'b', "byte-offset",           Arg_parser::no  },	// grep GNU
+    { 'B', "before-context",        Arg_parser::yes },	// grep GNU
+    { 'c', "count",                 Arg_parser::no  },	// grep
+    { 'C', "context",               Arg_parser::yes },	// grep GNU
+    { 'e', "regexp",                Arg_parser::yes },	// grep
+    { 'E', "extended-regexp",       Arg_parser::no  },	// grep
+    { 'f', "file ",                 Arg_parser::yes },	// grep
+    { 'F', "fixed-strings",         Arg_parser::no  },	// grep
+    { 'h', "no-filename",           Arg_parser::no  },	// grep GNU
+    { 'H', "with-filename",         Arg_parser::no  },	// grep GNU
+    { 'i', "ignore-case",           Arg_parser::no  },	// grep
+    { 'I',  0,                      Arg_parser::no  },	// grep GNU
+    { 'l', "files-with-matches",    Arg_parser::no  },	// grep
+    { 'L', "files-without-match",   Arg_parser::no  },	// grep GNU
+    { 'm', "max-count",             Arg_parser::yes },	// grep GNU
+    { 'n', "line-number",           Arg_parser::no  },	// grep
+    { 'o', "only-matching",         Arg_parser::no  },	// grep
+    { 'q', "quiet",                 Arg_parser::no  },
+    { 'r', "recursive",             Arg_parser::no  },
+    { 's', "no-messages",           Arg_parser::no  },	// grep
+    { 'v', "invert-match",          Arg_parser::no  },	// grep
+    { 'V', "version",               Arg_parser::no  },
+    { 'w', "word-regexp",           Arg_parser::no  },	// grep GNU
+    { 'x', "line-regexp",           Arg_parser::no  },	// grep
+    { help_opt,    "help",          Arg_parser::no  },
+    { verbose_opt, "verbose",       Arg_parser::no  },
+    { zgrep_opt,   "zgrep",         Arg_parser::no  },
+    {  0 ,  0,                      Arg_parser::no  } };
+
+  const Arg_parser::Option m_ztest_options[] =
     {
-    case '0': return 0;
-    case '1': return 1;
-    case '2': return 2;
-    case '3': return 3;
-    case '4': return 4;
-    case '5': return 5;
-    case '6': return 6;
-    case '7': return 7;
-    case '8': return 8;
-    case '9': return 9;
-    case 'a':
-    case 'A': return 0x0A;
-    case 'b':
-    case 'B': return 0x0B;
-    case 'c':
-    case 'C': return 0x0C;
-    case 'd':
-    case 'D': return 0x0D;
-    case 'e':
-    case 'E': return 0x0E;
-    case 'f':
-    case 'F': return 0x0F;
-    default: return -1;
-    }
-  }
-
-
-bool hex_to_data( const std::string & hex, std::string & data )
-  {
-  data.clear();
-  if( hex.size() == 0 || hex.size() % 2 != 0 ) return false;
-  for( unsigned int i = 0; 2 * i + 1 < hex.size(); ++i )
+    { 'h', "help",        Arg_parser::no  },
+    { 'q', "quiet",       Arg_parser::no  },
+    { 'r', "recursive",   Arg_parser::no  },
+    { 'v', "verbose",     Arg_parser::no  },
+    { 'V', "version",     Arg_parser::no  },
+    { ztest_opt, "ztest", Arg_parser::no  },
+    {  0 ,  0,            Arg_parser::no  } };
+
+  { // parse operation
+  const Arg_parser::Option operations[] =
     {
-    int uch = xtoi( hex[2*i] );
-    int lch = xtoi( hex[2*i+1] );
-    if( uch < 0 || lch < 0 ) return false;
-    data.push_back( ( uch << 4 ) | lch );
-    }
-  return true;
-  }
-
-
-int print_magic_type( const std::string & magic_type )
-  {
-  std::string data;
-
-  if( magic_type == "bzip2" ) std::printf( "BZh" );
-  else if( magic_type == "gzip" ) std::printf( "\x1F\x8B" );
-  else if( magic_type == "lzip" ) std::printf( "LZIP" );
-  else if( magic_type == "xz" ) std::printf( "%c7zXZ", '\xFD' );
-  else if( hex_to_data( magic_type, data ) ) std::printf( data.c_str() );
-  else return 1;
-  return 0;
-  }
-
+    { 'h', "help",              Arg_parser::no  },
+    { 'V', "version",           Arg_parser::no  },
+    { zcat_opt,  "zcat",        Arg_parser::no  },
+    { zgrep_opt, "zgrep",       Arg_parser::no  },
+    { ztest_opt, "ztest",       Arg_parser::no  },
+    {  0 ,  0,                  Arg_parser::no  } };
+
+  const Arg_parser parser( argv[1], ( argc > 2 ) ? argv[2] : 0, operations );
+  if( parser.error().size() )				// bad operation
+    { show_error( parser.error().c_str(), 0, true ); return 1; }
 
-int test_stdin_type( const int inhandle, const Pretty_print & pp )
-  {
-  unsigned char buf[5];
-  const char * msg = 0;
-  int i = 0;
-  if( readblock( inhandle, (char *)buf, 1 ) == 1 )
+  if( parser.arguments() > 0 )
     {
-    if( buf[0] == 0x1F )
+    switch( parser.code( 0 ) )
       {
-      if( readblock( inhandle, (char *)&buf[++i], 1 ) == 1 && buf[i] == 0x8B )
-        msg = "gzip";
-      }
-    else if( buf[0] == 'B' )
-      {
-      if( readblock( inhandle, (char *)&buf[++i], 1 ) == 1 && buf[i] == 'Z' &&
-          readblock( inhandle, (char *)&buf[++i], 1 ) == 1 && buf[i] == 'h' )
-        msg = "bzip2";
-      }
-    else if( buf[0] == 'L' )
-      {
-      if( readblock( inhandle, (char *)&buf[++i], 1 ) == 1 && buf[i] == 'Z' &&
-          readblock( inhandle, (char *)&buf[++i], 1 ) == 1 && buf[i] == 'I' &&
-          readblock( inhandle, (char *)&buf[++i], 1 ) == 1 && buf[i] == 'P' )
-        msg = "lzip";
-      }
-    else if( buf[0] == 0xFD )
-      {
-      if( readblock( inhandle, (char *)&buf[++i], 1 ) == 1 && buf[i] == '7' &&
-          readblock( inhandle, (char *)&buf[++i], 1 ) == 1 && buf[i] == 'z' &&
-          readblock( inhandle, (char *)&buf[++i], 1 ) == 1 && buf[i] == 'X' &&
-          readblock( inhandle, (char *)&buf[++i], 1 ) == 1 && buf[i] == 'Z' )
-        msg = "xz";
-      }
-    }
-  const int retval = ( msg ? 0 : 1 );
-  if( verbosity >= 0 )
-    {
-    if( verbosity >= 1 ) pp();
-    if( !msg )
-      {
-      char hexmsg[(2*sizeof buf)+1];
-      for( int j = 0; j <= i; ++j )
-        {
-        hexmsg[2*j] = xdigit( buf[j] >> 4 );
-        hexmsg[2*j+1] = xdigit( buf[j] & 0x0F );
-        }
-      hexmsg[2*i+2] = 0;
-      msg = hexmsg;
+      case  0 : break;
+      case 'h': show_help(); return 0;
+      case 'V': show_version(); return 0;
+      case zcat_opt  : program_mode = m_zcat; options = m_zcat_options;
+                       util_name = "zcat"; break;
+      case zgrep_opt : program_mode = m_zgrep; options = m_zgrep_options;
+                       util_name = "zgrep"; break;
+      case ztest_opt : program_mode = m_ztest; options = m_ztest_options;
+                       util_name = "ztest"; break;
+      default : internal_error( "uncaught option" );
       }
-    std::printf( "%s\n", msg );
     }
-  return retval;
-  }
 
+#if defined(__MSVCRT__) || defined(__OS2__)
+  _setmode( STDIN_FILENO, O_BINARY );
+  _setmode( STDOUT_FILENO, O_BINARY );
+#endif
 
-int test_type( const int inhandle, const Pretty_print & pp )
-  {
-  unsigned char buf[5];
-  const char * msg = 0;
-  const int size = readblock( inhandle, (char *)buf, sizeof buf );
-  if( size == (int)sizeof buf )
-    {
-    if( buf[0] == 0x1F && buf[1] == 0x8B )
-      msg = "gzip";
-    else if( buf[0] == 'B' && buf[1] == 'Z' && buf[2] == 'h' )
-      msg = "bzip2";
-    else if( buf[0] == 'L' && buf[1] == 'Z' && buf[2] == 'I' && buf[3] == 'P' )
-      msg = "lzip";
-    else if( buf[0] == 0xFD && buf[1] == '7' && buf[2] == 'z' && buf[3] == 'X' && buf[4] == 'Z' )
-      msg = "xz";
-    }
-  const int retval = ( msg ? 0 : 1 );
-  if( verbosity >= 0 )
+  if( program_mode == m_none )
     {
-    if( verbosity >= 1 ) pp();
-    if( !msg ) msg = "unknown";
-    std::printf( "%s\n", msg );
+    show_error( "You must specify the operation to be performed.", 0, true );
+    return 1;
     }
-  return retval;
-  }
-
-
-extern "C" void signal_handler( int ) throw()
-  {
-  show_error( "Control-C or similar caught, quitting." );
-  cleanup_and_fail( 0 );
-  }
-
+  } // end parse operation
 
-void set_signals() throw()
-  {
-  signal( SIGHUP, signal_handler );
-  signal( SIGINT, signal_handler );
-  signal( SIGTERM, signal_handler );
-  }
-
-} // end namespace
-
-
-int main( const int argc, const char * argv[] )
-  {
-  int inhandle = -1;
-  Mode program_mode = m_compress;
-  bool force = false;
-  bool keep_input_files = false;
-  bool to_stdout = false;
-  std::string input_filename;
-  std::string default_output_filename;
-  std::vector< std::string > filenames;
-  std::string magic_type;
-  invocation_name = argv[0];
-
-  const Arg_parser::Option options[] =
-    {
-    { 'c', "stdout",          Arg_parser::no  },
-    { 'd', "decompress",      Arg_parser::no  },
-    { 'f', "force",           Arg_parser::no  },
-    { 'h', "help",            Arg_parser::no  },
-    { 'k', "keep",            Arg_parser::no  },
-    { 'm', "magic",           Arg_parser::yes },
-    { 'o', "output",          Arg_parser::yes },
-    { 'q', "quiet",           Arg_parser::no  },
-    { 't', "test",            Arg_parser::no  },
-    { 'v', "verbose",         Arg_parser::no  },
-    { 'V', "version",         Arg_parser::no  },
-    {  0 ,  0,                Arg_parser::no  } };
-
-  Arg_parser parser( argc, argv, options );
+  const Arg_parser parser( argc, argv, options );
   if( parser.error().size() )				// bad option
-    { show_error( parser.error().c_str(), 0, true ); return 1; }
+    { show_error( parser.error().c_str(), 0, true );
+      return ( program_mode == m_zcat ) ? 1 : 2; }
 
   int argind = 0;
+  bool grep_list = false;
+  bool grep_show_name = true;
+  bool grep_pattern_found = false;
   for( ; argind < parser.arguments(); ++argind )
     {
     const int code = parser.code( argind );
-    if( !code ) break;					// no more options
-    const std::string & arg = parser.argument( argind );
-    switch( code )
+    const char * arg = parser.argument( argind ).c_str();
+    if( !code )
       {
-      case 'c': to_stdout = true; break;
-      case 'd': program_mode = m_decompress; break;
-      case 'f': force = true; break;
-      case 'h': show_help(); return 0;
-      case 'k': keep_input_files = true; break;
-      case 'm': magic_type = arg; break;
-      case 'o': default_output_filename = arg; break;
-      case 'q': verbosity = -1; break;
-      case 't': program_mode = m_test; break;
-      case 'v': if( verbosity < 4 ) ++verbosity; break;
-      case 'V': show_version(); return 0;
-      default : internal_error( "uncaught option" );
+      if( program_mode == m_zgrep && !grep_pattern_found )
+        { grep_args.push_back( arg ); grep_pattern_found = true; continue; }
+      else break;					// no more options
       }
-    }
+    switch( program_mode )
+      {
+      case m_none: internal_error( "invalid operation" );
+      case m_zcat:
+        switch( code )
+          {
+          case 'A': cat_options.show_ends = true;
+                    cat_options.show_nonprinting = true;
+                    cat_options.show_tabs = true; break;
+          case 'b': cat_options.number_lines = 1; break;
+          case 'c': break;
+          case 'd': break;
+          case 'e': cat_options.show_nonprinting = true;  // fall through
+          case 'E': cat_options.show_ends = true; break;
+          case 'f': break;
+          case 'h': show_zcat_help(); return 0;
+          case 'l': break;
+          case 'L': break;
+          case 'n': if( cat_options.number_lines == 0 )
+                      { cat_options.number_lines = 2; } break;
+          case 'q': verbosity = -1; break;
+          case 'r': recursive = true; break;
+          case 's': cat_options.squeeze_blank = true; break;
+          case 't': cat_options.show_nonprinting = true;  // fall through
+          case 'T': cat_options.show_tabs = true; break;
+          case 'v': cat_options.show_nonprinting = true; break;
+          case 'V': show_version( "Zcat" ); return 0;
+          case verbose_opt : if( verbosity < 4 ) ++verbosity; break;
+          case zcat_opt : break;
+          default : internal_error( "uncaught option" );
+          } break;
+      case m_zgrep:
+        switch( code )
+          {
+          case 'a': grep_args.push_back( "-a" ); break;
+          case 'A': grep_args.push_back( "-A" ); grep_args.push_back( arg ); break;
+          case 'b': grep_args.push_back( "-b" ); break;
+          case 'B': grep_args.push_back( "-B" ); grep_args.push_back( arg ); break;
+          case 'c': grep_args.push_back( "-c" ); break;
+          case 'C': grep_args.push_back( "-C" ); grep_args.push_back( arg ); break;
+          case 'e': grep_args.push_back( "-e" ); grep_args.push_back( arg );
+                    grep_pattern_found = true; break;
+          case 'E': grep_args.push_back( "-E" ); break;
+          case 'f': grep_args.push_back( "-f" ); grep_args.push_back( arg );
+                    grep_pattern_found = true; break;
+          case 'F': grep_args.push_back( "-F" ); break;
+          case 'h': grep_show_name = false; break;
+          case 'H': grep_show_name = true; break;
+          case 'i': grep_args.push_back( "-i" ); break;
+          case 'I': grep_args.push_back( "-I" ); break;
+          case 'l': grep_args.push_back( "-l" ); grep_list = true; break;
+          case 'L': grep_args.push_back( "-L" ); grep_list = true; break;
+          case 'm': grep_args.push_back( "-m" ); grep_args.push_back( arg ); break;
+          case 'n': grep_args.push_back( "-n" ); break;
+          case 'o': grep_args.push_back( "-o" ); break;
+          case 'q': grep_args.push_back( "-q" ); verbosity = -1; break;
+          case 'r': recursive = true; break;
+          case 's': grep_args.push_back( "-s" ); verbosity = -1; break;
+          case 'v': grep_args.push_back( "-v" ); break;
+          case 'V': show_version( "Zgrep" ); return 0;
+          case 'w': grep_args.push_back( "-w" ); break;
+          case 'x': grep_args.push_back( "-x" ); break;
+          case help_opt    : show_zgrep_help(); return 0;
+          case verbose_opt : if( verbosity < 4 ) ++verbosity; break;
+          case zgrep_opt   : break;
+          default : internal_error( "uncaught option" );
+          } break;
+      case m_ztest:
+        switch( code )
+          {
+          case 'h': show_ztest_help(); return 0;
+          case 'q': verbosity = -1; ztest_args.push_back( "-q" ); break;
+          case 'r': recursive = true; break;
+          case 'v': if( verbosity < 4 ) ++verbosity;
+                    ztest_args.push_back( "-v" ); break;
+          case 'V': show_version( "Ztest" ); return 0;
+          case ztest_opt : break;
+          default : internal_error( "uncaught option" );
+          } break;
+      }
+    } // end process options
 
-  if( magic_type.size() ) return print_magic_type( magic_type );
+  if( program_mode == m_zgrep && !grep_pattern_found )
+    { show_error( "Pattern not found.", 0, true ); return 2; }
 
   bool filenames_given = false;
   for( ; argind < parser.arguments(); ++argind )
@@ -725,96 +350,87 @@ int main( const int argc, const char * argv[] )
     }
 
   if( filenames.empty() ) filenames.push_back("-");
-  if( filenames_given ) set_signals();
 
-  Pretty_print pp( filenames );
-  if( program_mode == m_test )
-    outhandle = -1;
-
-  int retval = 0;
-  for( unsigned int i = 0; i < filenames.size(); ++i )
+  int retval = ( ( program_mode == m_zgrep ) ? 1 : 0 );
+  while( !filenames.empty() )
     {
-    struct stat in_stats;
-    output_filename.clear();
-
-    if( !filenames[i].size() || filenames[i] == "-" )
+    input_filename = filenames.front();
+    filenames.pop_front();
+    if( !input_filename.size() || input_filename == "-" )
       {
       input_filename.clear();
-      inhandle = STDIN_FILENO;
-      if( program_mode != m_test )
-        {
-        if( to_stdout || !default_output_filename.size() )
-          outhandle = STDOUT_FILENO;
-        else
-          {
-          if( program_mode == m_compress )
-            set_c_outname( default_output_filename );
-          else output_filename = default_output_filename;
-          if( !open_outstream( force ) )
-            {
-            if( outhandle == -1 && retval < 1 ) retval = 1;
-            close( inhandle ); inhandle = -1;
-            continue;
-            }
-          }
-        }
+      infd = STDIN_FILENO;
       }
     else
       {
-      input_filename = filenames[i];
-      const int eindex = extension_index( input_filename );
-      inhandle = open_instream( input_filename, &in_stats, program_mode,
-                                eindex, force, to_stdout );
-      if( inhandle < 0 ) { if( retval < 1 ) retval = 1; continue; }
-      if( program_mode != m_test )
+      if( recursive )
         {
-        if( to_stdout ) outhandle = STDOUT_FILENO;
-        else
+        struct stat st;
+        if( !stat( input_filename.c_str(), &st ) && S_ISDIR( st.st_mode ) )
           {
-          if( program_mode == m_compress )
-            set_c_outname( input_filename );
-          else set_d_outname( input_filename, eindex );
-          if( !open_outstream( force ) )
+          DIR * const dirp = opendir( input_filename.c_str() );
+          if( !dirp )
             {
-            if( outhandle == -1 && retval < 1 ) retval = 1;
-            close( inhandle ); inhandle = -1;
-            continue;
+            if( verbosity >= 0 )
+              std::fprintf( stderr, "%s: Can't open directory `%s': %s.\n",
+                util_name, input_filename.c_str(), std::strerror( errno ) );
+            if( retval < 1 ) retval = 1; continue;
             }
+          std::list< std::string > tmp_list;
+          while( true )
+            {
+            const struct dirent * const entryp = readdir( dirp );
+            if( !entryp ) { closedir( dirp ); break; }
+            std::string tmp_name( entryp->d_name );
+            if( tmp_name != "." && tmp_name != ".." )
+              tmp_list.push_back( input_filename + "/" + tmp_name );
+            }
+          filenames.splice( filenames.begin(), tmp_list );
+          continue;
           }
         }
+      infd = open_instream( input_filename, program_mode );
+      if( infd < 0 ) { if( retval < 1 ) retval = 1; continue; }
       }
 
-    if( !check_tty( inhandle, program_mode ) ) return 1;
-
-    if( output_filename.size() && !to_stdout && program_mode != m_test )
-      delete_output_on_interrupt = true;
-//    const struct stat * in_statsp = input_filename.size() ? &in_stats : 0;
-    pp.set_name( input_filename );
     int tmp = 0;
     switch( program_mode )
       {
-      case m_compress:
-        /*tmp = compress( inhandle, pp, in_statsp, &retval );*/ break;
-      case m_decompress:
-        /*tmp = decompress( inhandle, pp );*/ break;
-      case m_test:
-        if( inhandle == STDIN_FILENO )
-          tmp = test_stdin_type( inhandle, pp );
-        else tmp = test_type( inhandle, pp );
+      case m_none:
+        break;
+      case m_zcat:
+        tmp = cat( infd, input_filename, cat_options );
+        break;
+      case m_zgrep:
+        if( infd == STDIN_FILENO )
+          tmp = zgrep_stdin( infd, grep_args );
+        else tmp = zgrep_file( infd, input_filename, grep_args,
+                               grep_list, grep_show_name );
+        break;
+      case m_ztest:
+        if( infd == STDIN_FILENO )
+          tmp = ztest_stdin( infd, ztest_args );
+        else tmp = ztest_file( infd, input_filename, ztest_args );
         break;
       }
-    if( tmp > retval ) retval = tmp;
-    if( tmp && program_mode != m_test ) cleanup_and_fail( retval );
+    if( program_mode == m_zgrep )
+      { if( tmp == 0 || ( tmp == 2 && retval == 1 ) ) retval = tmp; }
+    else if( tmp > retval ) retval = tmp;
 
-//    if( delete_output_on_interrupt )
-//      close_and_set_permissions( in_statsp, &retval );
     if( input_filename.size() )
+      { close( infd ); infd = -1; }
+    }
+
+  if( std::fclose( stdout ) != 0 )
+    {
+    show_error( "Can't close stdout", errno );
+    switch( program_mode )
       {
-      close( inhandle ); inhandle = -1;
-      if( !keep_input_files && !to_stdout && program_mode != m_test )
-        std::remove( input_filename.c_str() );
+      case m_none: break;
+      case m_zcat: retval = 1; break;
+      case m_zgrep: if( retval != 0 || verbosity >= 0 ) retval = 2; break;
+      case m_ztest: if( retval == 0 ) retval = 1; break;
       }
     }
-  if( outhandle >= 0 ) close( outhandle );
   return retval;
   }
diff --git a/testsuite/check.sh b/testsuite/check.sh
index 94e9c71..073843e 100755
--- a/testsuite/check.sh
+++ b/testsuite/check.sh
@@ -1,6 +1,6 @@
 #! /bin/sh
 # check script for Zutils - Utilities dealing with compressed files
-# Copyright (C) 2009 Antonio Diaz Diaz.
+# Copyright (C) 2009, 2010 Antonio Diaz Diaz.
 #
 # This script is free software: you have unlimited permission
 # to copy, distribute and modify it.
@@ -16,11 +16,10 @@ ZGREP="${objdir}"/zgrep
 ZEGREP="${objdir}"/zegrep
 ZFGREP="${objdir}"/zfgrep
 ZTEST="${objdir}"/ztest
-ZUTILS="${objdir}"/zutils
 compressors="bzip2 gzip lzip"
 extensions="bz2 gz lz"
-framework_failure() { echo 'failure in testing framework'; exit 1; }
-compressor_needed() { echo "${compressors} are needed to run tests"; exit 1; }
+framework_failure() { echo "failure in testing framework" ; exit 1 ; }
+compressor_needed() { echo "${compressors} are needed to run tests" ; exit 1 ; }
 
 if [ ! -x "${ZCAT}" ] ; then
 	echo "${ZCAT}: cannot execute"
@@ -32,123 +31,181 @@ mkdir tmp
 cd "${objdir}"/tmp
 
 for i in ${compressors}; do
-	cat "${testdir}"/../COPYING > in || framework_failure
+	cat "${testdir}"/test.txt > in || framework_failure
 	$i in || compressor_needed
 done
 
-echo -n "testing zutils..."
-cat "${testdir}"/../COPYING > in || framework_failure
+printf "testing zutils-%s..." "$2"
+cat "${testdir}"/test.txt > in || framework_failure
 cat in > -in- || framework_failure
 cat in.lz > -in-.lz || framework_failure
-cat in in in in in > in5 || framework_failure
+cat in.lz > lz_only.lz || framework_failure
+cat in in in in in in > in6 || framework_failure
 fail=0
 
 
+printf "\ntesting   zcat-%s..." "$2"
 for i in ${extensions}; do
 	"${ZCAT}" in.$i > copy || fail=1
 	cmp in copy || fail=1
-	echo -n .
+	printf .
 done
 
 "${ZCAT}" < in > copy || fail=1
 cmp in copy || fail=1
-echo -n .
+printf .
 "${ZCAT}" < in.gz > copy || fail=1
 cmp in copy || fail=1
-echo -n .
+printf .
 "${ZCAT}" < in.bz2 > copy || fail=1
 cmp in copy || fail=1
-echo -n .
+printf .
 "${ZCAT}" < in.lz > copy || fail=1
 cmp in copy || fail=1
-echo -n .
+printf .
 "${ZCAT}" in > copy || fail=1
 cmp in copy || fail=1
-echo -n .
-"${ZCAT}" in in.gz in.bz2 in.lz -- -in- > copy5 || fail=1
-cmp in5 copy5 || fail=1
-echo -n .
+printf .
+"${ZCAT}" lz_only > copy || fail=1
+cmp in copy || fail=1
+printf .
+"${ZCAT}" in in.gz in.bz2 in.lz -- -in- -in-.lz > copy6 || fail=1
+cmp in6 copy6 || fail=1
+printf .
 
 
+printf "\ntesting   zcmp-%s..." "$2"
 for i in ${extensions}; do
 	"${ZCMP}" in.$i || fail=1
-	echo -n .
+	printf .
 	"${ZCMP}" in in.$i || fail=1
-	echo -n .
+	printf .
 	"${ZCMP}" in.$i in || fail=1
-	echo -n .
+	printf .
 done
 
-
+"${ZCMP}" - || fail=1
+printf .
+"${ZCMP}" in in || fail=1
+printf .
+"${ZCMP}" in || fail=1
+printf .
+"${ZCMP}" in.lz in.gz || fail=1
+printf .
+"${ZCMP}" in.gz -- -in-.lz || fail=1
+printf .
+"${ZCMP}" -- -in-.lz in.gz || fail=1
+printf .
+"${ZCMP}" in -- -in-.lz || fail=1
+printf .
+"${ZCMP}" -- -in- in.lz || fail=1
+printf .
+"${ZCMP}" in.lz -- -in- || fail=1
+printf .
+"${ZCMP}" -- -in-.lz in || fail=1
+printf .
+"${ZCMP}" -- -in- in || fail=1
+printf .
+"${ZCMP}" in -- -in- || fail=1
+printf .
+"${ZCMP}" lz_only.lz < in || fail=1
+printf .
+"${ZCMP}" in.lz - < in || fail=1
+printf .
+"${ZCMP}" - in.lz < in || fail=1
+printf .
+"${ZCMP}" in - < in.lz || fail=1
+printf .
+"${ZCMP}" - in < in.lz || fail=1
+printf .
+
+
+printf "\ntesting  zdiff-%s..." "$2"
 for i in ${extensions}; do
 	"${ZDIFF}" in.$i || fail=1
-	echo -n .
+	printf .
 	"${ZDIFF}" in in.$i || fail=1
-	echo -n .
+	printf .
 	"${ZDIFF}" in.$i in || fail=1
-	echo -n .
+	printf .
 done
 
+"${ZDIFF}" - || fail=1
+printf .
+"${ZDIFF}" in in || fail=1
+printf .
 "${ZDIFF}" in || fail=1
-echo -n .
+printf .
 "${ZDIFF}" in.lz in.gz || fail=1
-echo -n .
+printf .
 "${ZDIFF}" in.gz -- -in-.lz || fail=1
-echo -n .
+printf .
 "${ZDIFF}" -- -in-.lz in.gz || fail=1
-echo -n .
+printf .
 "${ZDIFF}" in -- -in-.lz || fail=1
-echo -n .
+printf .
 "${ZDIFF}" -- -in- in.lz || fail=1
-echo -n .
+printf .
 "${ZDIFF}" in.lz -- -in- || fail=1
-echo -n .
+printf .
 "${ZDIFF}" -- -in-.lz in || fail=1
-echo -n .
+printf .
 "${ZDIFF}" -- -in- in || fail=1
-echo -n .
+printf .
 "${ZDIFF}" in -- -in- || fail=1
-echo -n .
-
-
+printf .
+"${ZDIFF}" lz_only.lz < in || fail=1
+printf .
+"${ZDIFF}" in.lz - < in || fail=1
+printf .
+"${ZDIFF}" - in.lz < in || fail=1
+printf .
+"${ZDIFF}" in - < in.lz || fail=1
+printf .
+"${ZDIFF}" - in < in.lz || fail=1
+printf .
+
+
+printf "\ntesting  zgrep-%s..." "$2"
 for i in ${extensions}; do
-	"${ZGREP}" License in.$i 2>&1 > /dev/null || fail=1
-	echo -n .
+	"${ZGREP}" License in.$i > /dev/null || fail=1
+	"${ZGREP}" nx_pattern in.$i > /dev/null && fail=1
+	printf .
 done
 
-"${ZGREP}" License < in 2>&1 > /dev/null || fail=1
-echo -n .
-"${ZGREP}" License < in.gz 2>&1 > /dev/null || fail=1
-echo -n .
-"${ZGREP}" License < in.bz2 2>&1 > /dev/null || fail=1
-echo -n .
-"${ZGREP}" License < in.lz 2>&1 > /dev/null || fail=1
-echo -n .
-"${ZGREP}" License in 2>&1 > /dev/null || fail=1
-echo -n .
-"${ZGREP}" License -- -in- 2>&1 > /dev/null || fail=1
-echo -n .
-"${ZGREP}" License -- -in-.lz 2>&1 > /dev/null || fail=1
-echo -n .
-"${ZGREP}" License in in.gz in.bz2 in.lz -- -in- 2>&1 > /dev/null || fail=1
-echo -n .
-"${ZEGREP}" License in 2>&1 > /dev/null || fail=1
-echo -n .
-"${ZFGREP}" License in 2>&1 > /dev/null || fail=1
-echo -n .
-
+"${ZGREP}" -r License . > /dev/null || fail=1
+printf .
+"${ZGREP}" nx_pattern -r . in > /dev/null && fail=1
+printf .
+"${ZGREP}" License < in > /dev/null || fail=1
+printf .
+"${ZGREP}" License < in.gz > /dev/null || fail=1
+printf .
+"${ZGREP}" License < in.bz2 > /dev/null || fail=1
+printf .
+"${ZGREP}" License < in.lz > /dev/null || fail=1
+printf .
+"${ZGREP}" License in > /dev/null || fail=1
+printf .
+"${ZGREP}" License -- -in- > /dev/null || fail=1
+printf .
+"${ZGREP}" License -- -in-.lz > /dev/null || fail=1
+printf .
+"${ZGREP}" License in in.gz in.bz2 in.lz -- -in- > /dev/null || fail=1
+printf .
+"${ZEGREP}" License in > /dev/null || fail=1
+printf .
+"${ZFGREP}" License in > /dev/null || fail=1
+printf .
+
+
+printf "\ntesting  ztest-%s..." "$2"
 "${ZTEST}" in in.gz in.bz2 in.lz -- -in- || fail=1
-echo -n .
+printf .
 "${ZTEST}" -r . || fail=1
-echo -n .
-
-if [ "bzip2" != `"${ZUTILS}" -t in.bz2` ] ; then fail=1 ; fi
-echo -n .
-if [ "gzip" != `"${ZUTILS}" -t in.gz` ] ; then fail=1 ; fi
-echo -n .
-if [ "lzip" != `"${ZUTILS}" -t in.lz` ] ; then fail=1 ; fi
-echo -n .
-
+printf .
+printf "LZIPvs0000000000000000000000" | "${ZTEST}" 2>/dev/null && fail=1
+printf .
 
 echo
 if [ ${fail} = 0 ] ; then
diff --git a/testsuite/test.txt b/testsuite/test.txt
new file mode 100644
index 0000000..5b244d5
--- /dev/null
+++ b/testsuite/test.txt
@@ -0,0 +1,676 @@
+

+		    GNU GENERAL PUBLIC LICENSE

+		       Version 3, 29 June 2007

+

+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>

+ Everyone is permitted to copy and distribute verbatim copies

+ of this license document, but changing it is not allowed.

+

+			    Preamble

+

+  The GNU General Public License is a free, copyleft license for

+software and other kinds of works.

+

+  The licenses for most software and other practical works are designed

+to take away your freedom to share and change the works.  By contrast,

+the GNU General Public License is intended to guarantee your freedom to

+share and change all versions of a program--to make sure it remains free

+software for all its users.  We, the Free Software Foundation, use the

+GNU General Public License for most of our software; it applies also to

+any other work released this way by its authors.  You can apply it to

+your programs, too.

+

+  When we speak of free software, we are referring to freedom, not

+price.  Our General Public Licenses are designed to make sure that you

+have the freedom to distribute copies of free software (and charge for

+them if you wish), that you receive source code or can get it if you

+want it, that you can change the software or use pieces of it in new

+free programs, and that you know you can do these things.

+

+  To protect your rights, we need to prevent others from denying you

+these rights or asking you to surrender the rights.  Therefore, you have

+certain responsibilities if you distribute copies of the software, or if

+you modify it: responsibilities to respect the freedom of others.

+

+  For example, if you distribute copies of such a program, whether

+gratis or for a fee, you must pass on to the recipients the same

+freedoms that you received.  You must make sure that they, too, receive

+or can get the source code.  And you must show them these terms so they

+know their rights.

+

+  Developers that use the GNU GPL protect your rights with two steps:

+(1) assert copyright on the software, and (2) offer you this License

+giving you legal permission to copy, distribute and/or modify it.

+

+  For the developers' and authors' protection, the GPL clearly explains

+that there is no warranty for this free software.  For both users' and

+authors' sake, the GPL requires that modified versions be marked as

+changed, so that their problems will not be attributed erroneously to

+authors of previous versions.

+

+  Some devices are designed to deny users access to install or run

+modified versions of the software inside them, although the manufacturer

+can do so.  This is fundamentally incompatible with the aim of

+protecting users' freedom to change the software.  The systematic

+pattern of such abuse occurs in the area of products for individuals to

+use, which is precisely where it is most unacceptable.  Therefore, we

+have designed this version of the GPL to prohibit the practice for those

+products.  If such problems arise substantially in other domains, we

+stand ready to extend this provision to those domains in future versions

+of the GPL, as needed to protect the freedom of users.

+

+  Finally, every program is threatened constantly by software patents.

+States should not allow patents to restrict development and use of

+software on general-purpose computers, but in those that do, we wish to

+avoid the special danger that patents applied to a free program could

+make it effectively proprietary.  To prevent this, the GPL assures that

+patents cannot be used to render the program non-free.

+

+  The precise terms and conditions for copying, distribution and

+modification follow.

+

+		       TERMS AND CONDITIONS

+

+  0. Definitions.

+

+  "This License" refers to version 3 of the GNU General Public License.

+

+  "Copyright" also means copyright-like laws that apply to other kinds of

+works, such as semiconductor masks.

+ 

+  "The Program" refers to any copyrightable work licensed under this

+License.  Each licensee is addressed as "you".  "Licensees" and

+"recipients" may be individuals or organizations.

+

+  To "modify" a work means to copy from or adapt all or part of the work

+in a fashion requiring copyright permission, other than the making of an

+exact copy.  The resulting work is called a "modified version" of the

+earlier work or a work "based on" the earlier work.

+

+  A "covered work" means either the unmodified Program or a work based

+on the Program.

+

+  To "propagate" a work means to do anything with it that, without

+permission, would make you directly or secondarily liable for

+infringement under applicable copyright law, except executing it on a

+computer or modifying a private copy.  Propagation includes copying,

+distribution (with or without modification), making available to the

+public, and in some countries other activities as well.

+

+  To "convey" a work means any kind of propagation that enables other

+parties to make or receive copies.  Mere interaction with a user through

+a computer network, with no transfer of a copy, is not conveying.

+

+  An interactive user interface displays "Appropriate Legal Notices"

+to the extent that it includes a convenient and prominently visible

+feature that (1) displays an appropriate copyright notice, and (2)

+tells the user that there is no warranty for the work (except to the

+extent that warranties are provided), that licensees may convey the

+work under this License, and how to view a copy of this License.  If

+the interface presents a list of user commands or options, such as a

+menu, a prominent item in the list meets this criterion.

+

+  1. Source Code.

+

+  The "source code" for a work means the preferred form of the work

+for making modifications to it.  "Object code" means any non-source

+form of a work.

+

+  A "Standard Interface" means an interface that either is an official

+standard defined by a recognized standards body, or, in the case of

+interfaces specified for a particular programming language, one that

+is widely used among developers working in that language.

+

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+

diff --git a/zcat.cc b/zcat.cc
new file mode 100644
index 0000000..f813bbe
--- /dev/null
+++ b/zcat.cc
@@ -0,0 +1,213 @@
+/*  Zcat - decompress and concatenate files to standard output
+    Copyright (C) 2010 Antonio Diaz Diaz.
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+struct Cat_options
+  {
+  int number_lines;		// 0 = no, 1 = nonblank, 2 = all
+  bool show_ends;
+  bool show_nonprinting;
+  bool show_tabs;
+  bool squeeze_blank;
+
+  Cat_options() throw()
+    : number_lines( 0 ), show_ends( false ), show_nonprinting( false ),
+      show_tabs( false ), squeeze_blank( false ) {}
+  };
+
+
+class Line_number		// unlimited size line counter
+  {
+  std::string str;
+  int first_digit_pos;
+
+public:
+  Line_number() : str( "     0\t" ), first_digit_pos( 5 ) {}
+
+  void next()
+    {
+    for( int i = str.size() - 2; i >= first_digit_pos; --i )
+      {
+      if( str[i] < '9' ) { ++str[i]; return; }
+      str[i] = '0';
+      }
+    if( first_digit_pos > 0 ) str[--first_digit_pos] = '1';
+    else str.insert( 0, 1, '1' );
+    }
+
+  int sprint( uint8_t * const buf )
+    {
+    std::memcpy( buf, str.c_str(), str.size() );
+    return str.size();
+    }
+  };
+
+Line_number line_number;
+
+
+void show_zcat_help() throw()
+  {
+  std::printf( "Zcat copies each given file (\"-\" means standard input), to standard\n" );
+  std::printf( "output. If any given file is compressed, its uncompressed content is\n" );
+  std::printf( "used. If a given file does not exist, and its name does not end with one\n" );
+  std::printf( "of the known extensions, zcat tries the compressed file names\n" );
+  std::printf( "corresponding to the supported compressors. If no files are specified,\n" );
+  std::printf( "data is read from standard input, decompressed if needed, and sent to\n" );
+  std::printf( "standard output. Data read from standard input must be of the same type;\n" );
+  std::printf( "all uncompressed or all compressed with the same compressor.\n" );
+  std::printf( "The supported compressors are bzip2, gzip, lzip and xz.\n" );
+  std::printf( "\nUsage: zcat [options] [files]\n" );
+  std::printf( "\nExit status is 0 if no errors occurred, 1 otherwise.\n" );
+  std::printf( "\nOptions:\n" );
+  std::printf( "  -h, --help                 display this help and exit\n" );
+  std::printf( "  -V, --version              output version information and exit\n" );
+  std::printf( "  -A, --show-all             equivalent to `-vET'\n" );
+  std::printf( "  -b, --number-nonblank      number nonblank output lines\n" );
+  std::printf( "  -e                         equivalent to `-vE'\n" );
+  std::printf( "  -E, --show-ends            display `$' at end of each line\n" );
+  std::printf( "  -n, --number               number all output lines\n" );
+  std::printf( "  -q, --quiet                suppress all messages\n" );
+  std::printf( "  -r, --recursive            operate recursively on directories\n" );
+  std::printf( "  -s, --squeeze-blank        never more than one single blank line\n" );
+  std::printf( "  -t                         equivalent to `-vT'\n" );
+  std::printf( "  -T, --show-tabs            display TAB characters as `^I'\n" );
+  std::printf( "  -v, --show-nonprinting     use `^' and `M-' notation, except for LF and TAB\n" );
+  std::printf( "      --verbose              verbose mode (show error messages)\n" );
+  show_help_addr();
+  }
+
+
+int do_cat( const int infd, const int buffer_size,
+            uint8_t * const inbuf, uint8_t * const outbuf,
+            const std::string & input_filename,
+            const Cat_options & cat_options )
+  {
+  static int at_bol = 1;	// at begin of line. 0 = false, 1 = true,
+				// 2 = at begin of second blank line.
+  int inpos = 0;		// positions in buffers
+  int outpos = 0;
+  int rd = -1;			// bytes read by the last readblock
+  unsigned char c;
+
+  while( true )
+    {
+    do {
+      if( outpos >= buffer_size )
+        {
+        if( writeblock( STDOUT_FILENO, outbuf, outpos ) != outpos )
+          { show_error( "Write error", errno ); return 1; }
+        outpos = 0;
+        }
+      if( inpos > rd )			// inbuf is empty
+        {
+        rd = readblock( infd, inbuf, buffer_size );
+        if( rd != buffer_size && errno )
+          {
+          if( verbosity >= 0 )
+            std::fprintf( stderr, "%s: Error reading file `%s': %s.\n",
+                          util_name, input_filename.c_str(),
+                          std::strerror( errno ) );
+          return 1;
+          }
+        if( rd == 0 )
+          {
+          if( writeblock( STDOUT_FILENO, outbuf, outpos ) != outpos )
+            { show_error( "Write error", errno ); return 1; }
+          outpos = 0;
+          return 0;
+          }
+        inpos = 0;
+        inbuf[rd] = '\n';		// sentinel newline
+        }
+      else				// a real newline was found
+        {
+        if( at_bol > 1 )
+          {
+          if( cat_options.squeeze_blank ) { c = inbuf[inpos++]; continue; }
+          }
+        else ++at_bol;
+        if( at_bol > 1 && cat_options.number_lines == 2 )
+          {
+          line_number.next();
+          outpos += line_number.sprint( &outbuf[outpos] );
+          }
+        if( cat_options.show_ends ) outbuf[outpos++] = '$';
+        outbuf[outpos++] = '\n';		// output the newline
+        }
+      c = inbuf[inpos++];
+      }
+    while( c == '\n' );
+
+    if( at_bol > 0 && cat_options.number_lines )
+      {
+      line_number.next();
+      outpos += line_number.sprint( &outbuf[outpos] );
+      }
+    at_bol = 0;
+
+    // the loops below continue until a newline (real or sentinel) is found
+
+    if( cat_options.show_nonprinting )
+      while( true )
+        {
+        if( c < 32 || c >= 127 )
+          {
+          if( c == '\n' ) break;
+          if( c != '\t' || cat_options.show_tabs )
+            {
+            if( c >= 128 )
+              { c -= 128; outbuf[outpos++] = 'M'; outbuf[outpos++] = '-'; }
+            if( c < 32 ) { c += 64; outbuf[outpos++] = '^'; }
+            else if( c == 127 ) { c = '?'; outbuf[outpos++] = '^'; }
+            }
+          }
+        outbuf[outpos++] = c;
+        c = inbuf[inpos++];
+        }
+    else				// not quoting
+      while( c != '\n' )
+        {
+        if( c == '\t' && cat_options.show_tabs )
+          { c += 64; outbuf[outpos++] = '^'; }
+        outbuf[outpos++] = c;
+        c = inbuf[inpos++];
+        }
+    }
+  }
+
+
+int cat( int infd, const std::string & input_filename,
+         const Cat_options & cat_options )
+  {
+  enum { buffer_size = 4096 };
+  // buffer with space for sentinel newline at the end
+  uint8_t * const inbuf = new uint8_t[buffer_size+1];
+  // buffer with space for character quoting and 255-digit line number
+  uint8_t * const outbuf = new uint8_t[(4*buffer_size)+256];
+  pid_t pid = 0;
+  int retval = 0;
+  if( !set_data_feeder( &infd, &pid ) ) retval = 1;
+  else
+    {
+    retval = do_cat( infd, buffer_size, inbuf, outbuf,
+                     input_filename, cat_options );
+    if( pid && wait_for_child( pid, "data feeder" ) != 0 ) retval = 1;
+    if( close( infd ) != 0 )
+      { show_error( "Can't close output of data feeder", errno ); retval = 1; }
+    }
+  delete[] inbuf; delete[] outbuf;
+  return retval;
+  }
diff --git a/zcat.in b/zcat.in
index 2284c97..d88eef1 100644
--- a/zcat.in
+++ b/zcat.in
@@ -1,115 +1,3 @@
 #! /bin/sh
-# Zcat - Cat wrapper for compressed files.
-# Copyright (C) 2009 Antonio Diaz Diaz.
-#
-# This script is free software: you have unlimited permission
-# to copy, distribute and modify it.
-
-LC_ALL=C
-export LC_ALL
-args=
-gz_args=
-xz_args=
-recursive=0
-two_hyphens=0
-
-# Loop over args until a filename is found
-while [ -n "$1" ] ; do
-
-	case "$1" in
-	--help | --he* | -h)
-		echo "Zcat - Cat wrapper for compressed files."
-		echo
-		echo "Zcat is a wrapper script around the cat command that allows transparent"
-		echo "concatenation of any combination of compressed and non-compressed files."
-		echo "If any given file is compressed, its uncompressed content is used. If a"
-		echo "given file does not exist, zcat tries the compressed file names"
-		echo "corresponding to the supported compressors. If no files are specified,"
-		echo "data is read from standard input, decompressed if needed, and sent to"
-		echo "stdout. Data read from standard input must be of the same type; all"
-		echo "uncompressed or all compressed with the same compressor."
-		echo "The supported compressors are bzip2, gzip, lzip and xz."
-		echo
-		echo "Usage: $0 [OPTIONS] [CAT_OPTIONS] [FILES]"
-		echo
-		echo "CAT_OPTIONS are passed directly to cat."
-		echo "The exit status from cat is preserved."
-		echo
-		echo "Options:"
-		echo "  -h, --help          display this help and exit"
-		echo "  -V, --version       output version information and exit"
-		echo "  -r, --recursive     operate recursively on directories"
-		echo
-		echo "Report bugs to zutils-bug@nongnu.org"
-		echo "Zutils home page: http://www.nongnu.org/zutils/zutils.html"
-		exit 0 ;;
-	--version | --ve* | -V)
-		echo "Zcat (zutils) VERSION"
-		echo "Copyright (C) 2009 Antonio Diaz Diaz."
-		echo "This script is free software: you have unlimited permission"
-		echo "to copy, distribute and modify it."
-		exit 0 ;;
-	- | -c | --st* | -d | --de* | -f | --fo* | -q | --qu* | -L | --lic* )
-		;;
-	-l | --lis*)
-		gz_args="${gz_args} $1"; xz_args="${xz_args} $1" ;;
-	-r | --re*)
-		recursive=1 ;;
-	--)
-		shift ; two_hyphens=1 ; break ;;
-	-?*)
-		args="${args} $1" ;;
-	 *)
-		break ;;
-	esac
-	shift
-done
-
-if [ $# = 0 ] ; then
-	bindir=`echo "$0" | sed -e 's,[^/]*$,,'`
-	prog_name=`"${bindir}"zutils -t`
-	case "${prog_name}" in
-	bzip2)	prog="bzip2 -cdfq" ;;
-	gzip)	prog="gzip -cdfq ${gz_args}" ;;
-	lzip)	prog="lzip -cdfq" ;;
-	xz)	prog="xz -cdfq ${xz_args}" ;;
-	*)	prog=cat ;;
-	esac
-	{ "${bindir}"zutils -m ${prog_name} ; cat ; } | ${prog} | cat ${args}
-	exit $?
-fi
-
-retval=0
-for i in "$@" ; do
-	if [ "$i" = "--" ] && [ ${two_hyphens} = 0 ] ; then two_hyphens=1
-	else
-		if [ ! -f "$i" ] ; then
-			if [ -f "$i.gz" ] ;    then i="$i.gz"
-			elif [ -f "$i.bz2" ] ; then i="$i.bz2"
-			elif [ -f "$i.lz" ] ;  then i="$i.lz"
-			elif [ -f "$i.xz" ] ;  then i="$i.xz"
-			elif [ ${recursive} = 1 ] && [ -d "$i" ] ; then
-				find "$i" -type f -exec "$0" '{}' ';'
-				continue
-			else
-				echo "$0: File \"$i\" not found or not a regular file" 1>&2
-				if [ ${retval} = 0 ] ; then retval=1 ; fi
-				continue
-			fi
-		fi
-		bindir=`echo "$0" | sed -e 's,[^/]*$,,'`
-		prog_name=`"${bindir}"zutils -t -- "$i"`
-		case "${prog_name}" in
-		bzip2)	prog="bzip2 -cdfq" ;;
-		gzip)	prog="gzip -cdfq ${gz_args}" ;;
-		lzip)	prog="lzip -cdfq" ;;
-		xz)	prog="xz -cdfq ${xz_args}" ;;
-		*)	prog=cat ;;
-		esac
-		${prog} -- "$i" | cat ${args}
-		r=$?
-		if [ $r != 0 ] ; then retval=$r ; fi
-	fi
-done
-
-exit ${retval}
+bindir=`echo "$0" | sed -e 's,[^/]*$,,'`
+exec "${bindir}"zutils --zcat "$@"
diff --git a/zcmp.cc b/zcmp.cc
new file mode 100644
index 0000000..caa7852
--- /dev/null
+++ b/zcmp.cc
@@ -0,0 +1,502 @@
+/*  Zcmp - decompress and compare two files byte by byte
+    Copyright (C) 2010 Antonio Diaz Diaz.
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#define _FILE_OFFSET_BITS 64
+
+#include <cctype>
+#include <cerrno>
+#include <climits>
+#include <csignal>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <string>
+#include <vector>
+#include <fcntl.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#if defined(__MSVCRT__) || defined(__OS2__)
+#include <io.h>
+#endif
+
+#include "arg_parser.h"
+#include "zutils.h"
+
+#if CHAR_BIT != 8
+#error "Environments where CHAR_BIT != 8 are not supported."
+#endif
+
+#ifndef LLONG_MAX
+#define LLONG_MAX  0x7FFFFFFFFFFFFFFFLL
+#endif
+#ifndef LLONG_MIN
+#define LLONG_MIN  (-LLONG_MAX - 1LL)
+#endif
+#ifndef ULLONG_MAX
+#define ULLONG_MAX 0xFFFFFFFFFFFFFFFFULL
+#endif
+
+
+namespace {
+
+#ifdef O_BINARY
+const int o_binary = O_BINARY;
+#else
+const int o_binary = 0;
+#endif
+
+struct { const char * from; const char * to; } const known_extensions[] = {
+  { ".bz2",  ""     },
+  { ".tbz",  ".tar" },
+  { ".tbz2", ".tar" },
+  { ".gz",   ""     },
+  { ".tgz",  ".tar" },
+  { ".lz",   ""     },
+  { ".tlz",  ".tar" },
+  { ".xz",   ""     },
+  { ".txz",  ".tar" },
+  { 0,       0      } };
+
+
+void show_help() throw()
+  {
+  std::printf( "Zcmp compares two files (\"-\" means standard input), and if they\n" );
+  std::printf( "differ, tells the first byte and line number where they differ. Bytes\n" );
+  std::printf( "and lines are numbered starting with 1. If any given file is compressed,\n" );
+  std::printf( "its uncompressed content is used. Compressed files are uncompressed on\n" );
+  std::printf( "the fly; no temporary files are created.\n" );
+  std::printf( "The supported compressors are bzip2, gzip, lzip and xz.\n" );
+  std::printf( "\nUsage: zcmp [options] file1 [file2]\n" );
+  std::printf( "\nCompares <file1> to <file2>. If <file2> is omitted zcmp tries the\n" );
+  std::printf( "following:\n" );
+  std::printf( "If <file1> is compressed, compares <file1> to the file with the\n" );
+  std::printf( "corresponding decompressed file name (removes the extension from\n" );
+  std::printf( "<file1>).\n" );
+  std::printf( "If <file1> is not compressed, compares <file1> to the uncompressed\n" );
+  std::printf( "contents of <file1>.[bz2|gz|lz|xz] (the first one that is found).\n" );
+  std::printf( "If no suitable file is found, compares <file1> to data read from\n" );
+  std::printf( "standard input.\n" );
+  std::printf( "\nExit status is 0 if inputs are identical, 1 if different, 2 if trouble.\n" );
+  std::printf( "\nOptions:\n" );
+  std::printf( "  -h, --help                       display this help and exit\n" );
+  std::printf( "  -V, --version                    output version information and exit\n" );
+  std::printf( "  -b, --print-bytes                print differing bytes\n" );
+  std::printf( "  -i, --ignore-initial=<n>[,<n2>]  ignore differences in the first <n> bytes\n" );
+  std::printf( "  -l, --list                       list position, value of all differing bytes\n" );
+  std::printf( "  -n, --bytes=<n>                  compare at most <n> bytes\n" );
+  std::printf( "  -q, --quiet                      suppress all messages\n" );
+  std::printf( "  -s, --silent                     (same as --quiet)\n" );
+  std::printf( "  -v, --verbose                    verbose mode (same as --list)\n" );
+  std::printf( "Numbers may be followed by a multiplier: k = kB = 10^3 = 1000,\n" );
+  std::printf( "Ki = KiB = 2^10 = 1024, M = 10^6, Mi = 2^20, G = 10^9, Gi = 2^30, etc...\n" );
+  show_help_addr();
+  }
+
+
+long long getnum( const char * const ptr, const char ** const tailp = 0,
+                  const long long llimit = LLONG_MIN + 1,
+                  const long long ulimit = LLONG_MAX ) throw()
+  {
+  errno = 0;
+  char * tail;
+  long long result = strtoll( ptr, &tail, 0 );
+  if( tail == ptr )
+    {
+    show_error( "Bad or missing numerical argument.", 0, true );
+    std::exit( 2 );
+    }
+
+  if( !errno && tail[0] && std::isalpha( tail[0] ) )
+    {
+    int factor = ( tail[1] == 'i' ) ? 1024 : 1000;
+    int exponent = 0;
+    bool bad_multiplier = false;
+    switch( tail[0] )
+      {
+      case 'Y': exponent = 8; break;
+      case 'Z': exponent = 7; break;
+      case 'E': exponent = 6; break;
+      case 'P': exponent = 5; break;
+      case 'T': exponent = 4; break;
+      case 'G': exponent = 3; break;
+      case 'M': exponent = 2; break;
+      case 'K': if( factor == 1024 ) exponent = 1; else bad_multiplier = true;
+                break;
+      case 'k': if( factor == 1000 ) exponent = 1; else bad_multiplier = true;
+                break;
+      default : bad_multiplier = true;
+      }
+    if( bad_multiplier )
+      {
+      show_error( "Bad multiplier in numerical argument.", 0, true );
+      std::exit( 2 );
+      }
+    for( int i = 0; i < exponent; ++i )
+      {
+      if( LLONG_MAX / factor >= llabs( result ) ) result *= factor;
+      else { errno = ERANGE; break; }
+      }
+    }
+  if( !errno && ( result < llimit || result > ulimit ) ) errno = ERANGE;
+  if( errno )
+    {
+    show_error( "Numerical argument out of limits." );
+    std::exit( 2 );
+    }
+  if( tailp ) *tailp = tail;
+  return result;
+  }
+
+
+int open_instream( const std::string & input_filename ) throw()
+  {
+  int infd = open( input_filename.c_str(), O_RDONLY | o_binary );
+  if( infd < 0 && verbosity >= 0 )
+    std::fprintf( stderr, "%s: Can't open input file `%s': %s.\n",
+                  util_name, input_filename.c_str(), std::strerror( errno ) );
+  return infd;
+  }
+
+
+int open_other_instream( std::string & name ) throw()
+  {
+  for( int i = 0; known_extensions[i].from; ++i )
+    {					// search uncompressed version
+    const std::string from( known_extensions[i].from );
+    if( name.size() > from.size() &&
+        name.compare( name.size() - from.size(), from.size(), from ) == 0 )
+      {
+      name.resize( name.size() - from.size() );
+      name += known_extensions[i].to;
+      return open( name.c_str(), O_RDONLY | o_binary );
+      }
+    }
+  for( int i = 0; simple_extensions[i]; ++i )
+    {					// search compressed version
+    const std::string s( name + simple_extensions[i] );
+    const int infd = open( s.c_str(), O_RDONLY | o_binary );
+    if( infd >= 0 ) { name = s; return infd; }
+    }
+  return -1;
+  }
+
+
+bool check_identical( const char * const name1, const char * const name2 ) throw()
+  {
+  if( !std::strcmp( name1, name2 ) ) return true;
+  struct stat stat1, stat2;
+  if( stat( name1, &stat1 ) || stat( name2, &stat2 ) ) return false;
+  return ( stat1.st_ino == stat2.st_ino && stat1.st_dev == stat2.st_dev );
+  }
+
+
+void parse_ignore_initial( const char * const arg, long long ignore_initial[2] )
+  {
+  const char * tail;
+  ignore_initial[0] = getnum( arg, &tail, 0 );
+  if( *tail == ',' || *tail == ':' )
+    ignore_initial[1] = getnum( ++tail, 0, 0 );
+  else ignore_initial[1] = ignore_initial[0];
+  }
+
+
+bool skip_ignore_initial( const long long ignore_initial, const int infd )
+  {
+  if( ignore_initial > 0 )
+    {
+    enum { buffer_size = 4096 };
+    long long rest = ignore_initial;
+    uint8_t buffer[buffer_size];
+    while( rest > 0 )
+      {
+      const int size = std::min( rest, (long long)buffer_size );
+      const int rd = readblock( infd, buffer, size );
+      if( rd != size && errno ) return false;
+      if( rd < size ) break;
+      rest -= rd;
+      }
+    }
+  return true;
+  }
+
+
+// Put into buf the unsigned char c, making unprintable bytes
+// visible by quoting like cat -t does.
+void sprintc( char * const buf, unsigned char c )
+  {
+  int i = 0;
+
+  if( c < 32 || c >= 127 )
+    {
+    if( c >= 128 ) { c -= 128; buf[i++] = 'M'; buf[i++] = '-'; }
+    if( c < 32 ) { c += 64; buf[i++] = '^'; }
+    else if( c == 127 ) { c = '?'; buf[i++] = '^'; }
+    }
+  buf[i++] = c;
+  buf[i++] = 0;
+  }
+
+
+int block_compare( const uint8_t * const buffer0,
+                   const uint8_t * const buffer1,
+                   long long * line_numberp )
+  {
+  const uint8_t * p0 = buffer0;
+  const uint8_t * p1 = buffer1;
+  if( verbosity == 0 )
+    {
+    int nl_count = 0;
+    while( *p0 == *p1 )
+      { if( *p0 == '\n' ) { ++nl_count; } ++p0; ++p1; }
+    *line_numberp += nl_count;
+    }
+  else while( *p0 == *p1 ) { ++p0; ++p1; }
+  return p0 - buffer0;
+  }
+
+
+int cmp( const long long max_size, const int infd[2],
+         const std::string filenames[2], const bool print_bytes )
+  {
+  enum { buffer_size = 4096 };
+  long long byte_number = 1;
+  long long line_number = 1;
+  long long rest = max_size;	// remaining number of bytes to compare
+  // buffers with space for sentinels at the end
+  uint8_t * const buffer0 = new uint8_t[2*(buffer_size+1)];
+  uint8_t * const buffer1 = buffer0 + buffer_size + 1;
+  uint8_t * buffer[2];
+  buffer[0] = buffer0; buffer[1] = buffer1;
+  int different = 0;
+
+  while( rest > 0 )
+    {
+    const int size = std::min( rest, (long long)buffer_size );
+    int rd[2];			// number of bytes read from each file
+    for( int i = 0; i < 2; ++i )
+      {
+      rd[i] = readblock( infd[i], buffer[i], size );
+      if( rd[i] != size && errno )
+        {
+        if( verbosity >= 0 )
+          std::fprintf( stderr, "%s: Error reading file `%s': %s.\n",
+                        util_name, filenames[i].c_str(), std::strerror( errno ) );
+        return 2;
+        }
+      }
+    rest -= size;
+
+    buffer0[rd[0]] = ~buffer1[rd[0]];	// sentinels for the block compare
+    buffer1[rd[1]] = ~buffer0[rd[1]];
+
+    int first_diff = block_compare( buffer0, buffer1, &line_number );
+    byte_number += first_diff;
+    const int min_rd = std::min( rd[0], rd[1] );
+
+    if( first_diff < min_rd )
+      {
+      if( verbosity < 0 ) return 1;		// return status only
+      if( verbosity == 0 )			// show first difference
+        {
+        if( !print_bytes )
+          std::printf( "%s %s differ: byte %lld, line %lld\n",
+                       filenames[0].c_str(), filenames[1].c_str(),
+                       byte_number, line_number );
+        else
+          {
+          const unsigned char c0 = buffer0[first_diff];
+          const unsigned char c1 = buffer1[first_diff];
+          char buf0[5], buf1[5];
+          sprintc( buf0, c0 ); sprintc( buf1, c1 );
+          std::printf( "%s %s differ: byte %lld, line %lld is %3o %s %3o %s\n",
+                       filenames[0].c_str(), filenames[1].c_str(),
+                       byte_number, line_number, c0, buf0, c1, buf1 );
+          }
+        return 1;
+        }
+      else			// verbosity > 0 ; show all differences
+        {
+        different = 1;
+        for( ; first_diff < min_rd; ++byte_number, ++first_diff )
+          {
+          const unsigned char c0 = buffer0[first_diff];
+          const unsigned char c1 = buffer1[first_diff];
+          if( c0 != c1 )
+            {
+            if( !print_bytes )
+              std::printf( "%lld %3o %3o\n", byte_number, c0, c1 );
+            else
+              {
+              char buf0[5], buf1[5];
+              sprintc( buf0, c0 ); sprintc( buf1, c1 );
+              std::printf( "%lld %3o %-4s %3o %s\n",
+                           byte_number, c0, buf0, c1, buf1 );
+              }
+            }
+          }
+        }
+      }
+
+    if( rd[0] != rd[1] )
+      {
+      if( verbosity >= 0 )
+        std::fprintf( stderr, "%s: EOF on %s\n",
+                      util_name, filenames[rd[1]<rd[0]].c_str() );
+        return 1;
+      }
+    if( min_rd != buffer_size ) break;
+    }
+
+  delete[] buffer0;
+  return different;
+  }
+
+} // end namespace
+
+
+int main( const int argc, const char * const argv[] )
+  {
+  // number of initial bytes ignored for each file
+  long long ignore_initial[2] = { 0, 0 };
+  long long max_size = LLONG_MAX;
+  bool print_bytes = false;
+  invocation_name = argv[0];
+  util_name = "zcmp";
+
+  const Arg_parser::Option options[] =
+    {
+    { 'b', "print-bytes",    Arg_parser::no  },
+    { 'h', "help",           Arg_parser::no  },
+    { 'i', "ignore-initial", Arg_parser::yes },
+    { 'l', "list",           Arg_parser::no  },
+    { 'n', "bytes",          Arg_parser::yes },
+    { 'q', "quiet",          Arg_parser::no  },
+    { 's', "silent",         Arg_parser::no  },
+    { 'v', "verbose",        Arg_parser::no  },
+    { 'V', "version",        Arg_parser::no  },
+    {  0 ,  0,               Arg_parser::no  } };
+
+  const Arg_parser parser( argc, argv, options );
+  if( parser.error().size() )				// bad option
+    { show_error( parser.error().c_str(), 0, true ); return 2; }
+
+  int argind = 0;
+  for( ; argind < parser.arguments(); ++argind )
+    {
+    const int code = parser.code( argind );
+    if( !code ) break;					// no more options
+    const char * const arg = parser.argument( argind ).c_str();
+    switch( code )
+      {
+      case 'b': print_bytes = true; break;
+      case 'h': show_help(); return 0;
+      case 'i': parse_ignore_initial( arg, ignore_initial ); break;
+      case 'l': verbosity = 1; break;
+      case 'n': max_size = getnum( arg, 0, 0 ); break;
+      case 'q':
+      case 's': verbosity = -1; break;
+      case 'v': verbosity = 1; break;
+      case 'V': show_version( "Zcmp" ); return 0;
+      default : internal_error( "uncaught option" );
+      }
+    } // end process options
+
+#if defined(__MSVCRT__) || defined(__OS2__)
+  _setmode( STDIN_FILENO, O_BINARY );
+  _setmode( STDOUT_FILENO, O_BINARY );
+#endif
+
+  if( argind >= parser.arguments() )
+    { show_error( "No files given.", 0, true ); return 2; }
+  if( argind + 2 < parser.arguments() )
+    { show_error( "Too many files.", 0, true ); return 2; }
+
+  const int files = parser.arguments() - argind;
+  std::string filenames[2];		// file names of the two input files
+  filenames[0] = parser.argument( argind );
+  if( files == 2 ) filenames[1] = parser.argument( argind + 1 );
+
+  int infd[2];				// file descriptors of the two files
+  infd[0] = ( filenames[0] == "-" ) ?
+    STDIN_FILENO : open_instream( filenames[0] );
+  if( infd[0] < 0 ) return 2;
+
+  if( ( files == 1 && filenames[0] == "-" ) ||
+      ( files == 2 && check_identical( filenames[0].c_str(),
+                                       filenames[1].c_str() ) ) )
+    {
+    if( ignore_initial[0] == ignore_initial[1] ) return 0;
+    else { show_error( "Can't compare parts of same file." ); return 2; }
+    }
+
+  if( files == 2 )
+    {
+    infd[1] = ( filenames[1] == "-" ) ?
+      STDIN_FILENO : open_instream( filenames[1] );
+    if( infd[1] < 0 ) return 2;
+    }
+  else
+    {
+    filenames[1] = filenames[0];
+    infd[1] = open_other_instream( filenames[1] );
+    if( infd[1] < 0 ) { infd[1] = STDIN_FILENO; filenames[1] = "-"; }
+    }
+
+  int old_infd[2];		// copy of file descriptors of the two files
+  old_infd[0] = infd[0]; old_infd[1] = infd[1];
+  pid_t pid[2];
+  if( !set_data_feeder( &infd[0], &pid[0] ) ||
+      !set_data_feeder( &infd[1], &pid[1] ) )
+    return 2;
+
+  for( int i = 0; i < 2; ++i )
+    if( !skip_ignore_initial( ignore_initial[i], infd[i] ) )
+      {
+      if( verbosity >= 0 )
+        std::fprintf( stderr, "%s: Can't skip initial bytes from file `%s': %s.\n",
+                      util_name, filenames[i].c_str(), std::strerror( errno ) );
+      return 2;
+      }
+
+  int retval = cmp( max_size, infd, filenames, print_bytes );
+
+  if( ( ( pid[0] && wait_for_child( pid[0], "data feeder" ) != 0 ) ||
+        ( pid[1] && wait_for_child( pid[1], "data feeder" ) != 0 ) ) &&
+      retval == 0 )
+    retval = 2;
+
+  for( int i = 0; i < 2; ++i )
+    {
+    if( close( infd[i] ) != 0 )
+      { show_error( "Can't close output of data feeder", errno ); retval = 2; }
+    if( filenames[i] != "-" && close( old_infd[i] ) != 0 )
+      {
+      if( verbosity >= 0 )
+        std::fprintf( stderr, "%s: Can't close input file `%s': %s.\n",
+                      util_name, filenames[i].c_str(), std::strerror( errno ) );
+      retval = 2;
+      }
+    }
+  if( std::fclose( stdout ) != 0 )
+    {
+    show_error( "Can't close stdout", errno );
+    retval = 2;
+    }
+
+  return retval;
+  }
diff --git a/zcmp.in b/zcmp.in
deleted file mode 100644
index d2ad056..0000000
--- a/zcmp.in
+++ /dev/null
@@ -1,3 +0,0 @@
-#! /bin/sh
-bindir=`echo "$0" | sed -e 's,[^/]*$,,'`
-exec "${bindir}"zdiff --cmp "$@"
diff --git a/zdiff.cc b/zdiff.cc
new file mode 100644
index 0000000..d01f492
--- /dev/null
+++ b/zdiff.cc
@@ -0,0 +1,476 @@
+/*  Zdiff - decompress and compare two files line by line
+    Copyright (C) 2010 Antonio Diaz Diaz.
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#define _FILE_OFFSET_BITS 64
+
+#include <cctype>
+#include <cerrno>
+#include <climits>
+#include <csignal>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <string>
+#include <vector>
+#include <fcntl.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#if defined(__MSVCRT__) || defined(__OS2__)
+#include <io.h>
+#endif
+
+#include "arg_parser.h"
+#include "zutils.h"
+
+#if CHAR_BIT != 8
+#error "Environments where CHAR_BIT != 8 are not supported."
+#endif
+
+#ifndef LLONG_MAX
+#define LLONG_MAX  0x7FFFFFFFFFFFFFFFLL
+#endif
+#ifndef LLONG_MIN
+#define LLONG_MIN  (-LLONG_MAX - 1LL)
+#endif
+#ifndef ULLONG_MAX
+#define ULLONG_MAX 0xFFFFFFFFFFFFFFFFULL
+#endif
+
+
+namespace {
+
+std::string fifonames[2];	// names of the two fifos passed to diff
+
+#ifdef O_BINARY
+const int o_binary = O_BINARY;
+#else
+const int o_binary = 0;
+#endif
+
+struct { const char * from; const char * to; } const known_extensions[] = {
+  { ".bz2",  ""     },
+  { ".tbz",  ".tar" },
+  { ".tbz2", ".tar" },
+  { ".gz",   ""     },
+  { ".tgz",  ".tar" },
+  { ".lz",   ""     },
+  { ".tlz",  ".tar" },
+  { ".xz",   ""     },
+  { ".txz",  ".tar" },
+  { 0,       0      } };
+
+
+void show_help() throw()
+  {
+  std::printf( "Zdiff compares two files (\"-\" means standard input), and if they\n" );
+  std::printf( "differ, shows the differences line by line. If any given file is\n" );
+  std::printf( "compressed, its uncompressed content is used. Zdiff is a front end to\n" );
+  std::printf( "the diff program and has the limitation that messages from diff refer to\n" );
+  std::printf( "temporary filenames instead of those specified.\n" );
+  std::printf( "The supported compressors are bzip2, gzip, lzip and xz.\n" );
+  std::printf( "\nUsage: zdiff [options] file1 [file2]\n" );
+  std::printf( "\nCompares <file1> to <file2>. If <file2> is omitted zdiff tries the\n" );
+  std::printf( "following:\n" );
+  std::printf( "If <file1> is compressed, compares <file1> to the file with the\n" );
+  std::printf( "corresponding decompressed file name (removes the extension from\n" );
+  std::printf( "<file1>).\n" );
+  std::printf( "If <file1> is not compressed, compares <file1> to the uncompressed\n" );
+  std::printf( "contents of <file1>.[bz2|gz|lz|xz] (the first one that is found).\n" );
+  std::printf( "If no suitable file is found, compares <file1> to data read from\n" );
+  std::printf( "standard input.\n" );
+  std::printf( "\nExit status is 0 if inputs are identical, 1 if different, 2 if trouble.\n" );
+  std::printf( "\nOptions:\n" );
+  std::printf( "  -h, --help                    display this help and exit\n" );
+  std::printf( "  -V, --version                 output version information and exit\n" );
+  std::printf( "  -a, --text                    treat all files as text\n" );
+  std::printf( "  -b, --ignore-space-change     ignore changes in the amount of white space\n" );
+  std::printf( "  -B, --ignore-blank-lines      ignore changes whose lines are all blank\n" );
+  std::printf( "  -c                            use the context output format\n" );
+  std::printf( "  -C, --context=<n>             same as -c but use <n> lines of context\n" );
+  std::printf( "  -d, --minimal                 try hard to find a smaller set of changes\n" );
+  std::printf( "  -E, --ignore-tab-expansion    ignore changes due to tab expansion\n" );
+  std::printf( "  -i, --ignore-case             ignore case differences in file contents\n" );
+  std::printf( "  -p, --show-c-function         show which C function each change is in\n" );
+  std::printf( "  -q, --brief                   output only whether files differ\n" );
+  std::printf( "  -s, --report-identical-files  report when two files are identical\n" );
+  std::printf( "  -t, --expand-tabs             expand tabs to spaces in output\n" );
+  std::printf( "  -T, --initial-tab             make tabs line up by prepending a tab\n" );
+  std::printf( "  -u                            use the unified output format\n" );
+  std::printf( "  -U, --unified=<n>             same as -u but use <n> lines of context\n" );
+  std::printf( "  -w, --ignore-all-space        ignore all white space\n" );
+  std::printf( "Numbers may be followed by a multiplier: k = kB = 10^3 = 1000,\n" );
+  std::printf( "Ki = KiB = 2^10 = 1024, M = 10^6, Mi = 2^20, G = 10^9, Gi = 2^30, etc...\n" );
+  show_help_addr();
+  }
+
+
+int open_instream( const std::string & input_filename ) throw()
+  {
+  int infd = open( input_filename.c_str(), O_RDONLY | o_binary );
+  if( infd < 0 && verbosity >= 0 )
+    std::fprintf( stderr, "%s: Can't open input file `%s': %s.\n",
+                  util_name, input_filename.c_str(), std::strerror( errno ) );
+  return infd;
+  }
+
+
+int open_other_instream( std::string & name ) throw()
+  {
+  for( int i = 0; known_extensions[i].from; ++i )
+    {					// search uncompressed version
+    const std::string from( known_extensions[i].from );
+    if( name.size() > from.size() &&
+        name.compare( name.size() - from.size(), from.size(), from ) == 0 )
+      {
+      name.resize( name.size() - from.size() );
+      name += known_extensions[i].to;
+      return open( name.c_str(), O_RDONLY | o_binary );
+      }
+    }
+  for( int i = 0; simple_extensions[i]; ++i )
+    {					// search compressed version
+    const std::string s( name + simple_extensions[i] );
+    const int infd = open( s.c_str(), O_RDONLY | o_binary );
+    if( infd >= 0 ) { name = s; return infd; }
+    }
+  return -1;
+  }
+
+
+bool check_identical( const char * const name1, const char * const name2 ) throw()
+  {
+  if( !std::strcmp( name1, name2 ) ) return true;
+  struct stat stat1, stat2;
+  if( stat( name1, &stat1 ) || stat( name2, &stat2 ) ) return false;
+  return ( stat1.st_ino == stat2.st_ino && stat1.st_dev == stat2.st_dev );
+  }
+
+
+const char * my_basename( const char * filename ) throw()
+  {
+  const char * c = filename;
+  while( *c ) { if( *c == '/' ) { filename = c + 1; } ++c; }
+  return filename;
+  }
+
+
+void remove_fifos() throw()
+  {
+  if( fifonames[0].size() )
+    { std::remove( fifonames[0].c_str() ); fifonames[0].clear(); }
+  if( fifonames[1].size() )
+    { std::remove( fifonames[1].c_str() ); fifonames[1].clear(); }
+  }
+
+
+// Set fifonames[i] to "${TMPDIR}/<coded_pid><i>_<basename(filenames[i])>"
+// and create FIFOs.
+bool set_fifonames( const std::string filenames[2] )
+  {
+  enum { num_codes = 36 };
+  const char * const codes = "0123456789abcdefghijklmnopqrstuvwxyz";
+  const char * p = std::getenv( "TMPDIR" );
+  const int pid = getpid();
+
+  for( int i = 0; i < 2; ++i )
+    {
+    if( p ) fifonames[i] = p; else fifonames[i] = "/tmp";
+    fifonames[i] += '/';
+    int n = ( 2 * pid ) + i;
+    const unsigned int pos = fifonames[i].size();
+    do { fifonames[i].insert( pos, 1, codes[n % num_codes] );
+         n /= num_codes; }
+    while( n );
+    fifonames[i] += '_';
+    fifonames[i] += my_basename( filenames[i].c_str() );
+    }
+
+  for( int i = 0; i < 2; ++i )
+    if( mkfifo( fifonames[i].c_str(), S_IRUSR | S_IWUSR ) != 0 )
+      {
+      if( errno == EEXIST )
+        {
+        std::remove( fifonames[i].c_str() );
+        if( mkfifo( fifonames[i].c_str(), S_IRUSR | S_IWUSR ) == 0 )
+          continue;
+        }
+      if( verbosity >= 0 )
+        std::fprintf( stderr, "%s: Can't create FIFO `%s': %s.\n",
+                      util_name, fifonames[i].c_str(), std::strerror( errno ) );
+      return false;
+      }
+  return true;
+  }
+
+
+bool set_data_feeder( const std::string & fifoname, const int infd,
+                      pid_t * const pidp )
+  {
+  std::string file_type;
+  const uint8_t * magic_data;
+  int magic_size;
+  const bool compressed =
+    test_format( infd, file_type, &magic_data, &magic_size );
+
+  if( compressed )			// compressed with `file_type'
+    {
+    int fda[2];				// pipe from feeder to decompressor
+    if( pipe( fda ) < 0 )
+      { show_error( "Can't create pipe", errno ); return false; }
+    const pid_t pid = fork();
+    if( pid == 0 )			// child (decompressor feeder)
+      {
+      const pid_t pid2 = fork();
+      if( pid2 == 0 )			// grandchild (decompressor)
+        {
+        const int outfd = open( fifoname.c_str(), O_WRONLY | o_binary );
+        if( outfd < 0 )
+          {
+          if( verbosity >= 0 )
+            std::fprintf( stderr, "%s: Can't open FIFO `%s' for writing: %s.\n",
+                        util_name, fifoname.c_str(), std::strerror( errno ) );
+          _exit( 2 );
+          }
+        if( dup2( fda[0], STDIN_FILENO ) >= 0 &&
+            dup2( outfd, STDOUT_FILENO ) >= 0 &&
+            close( fda[0] ) == 0 && close( fda[1] ) == 0 &&
+            close( outfd ) == 0 )
+          execlp( file_type.c_str(), file_type.c_str(), "-cdfq", (char *)0 );
+        if( verbosity >= 0 )
+          std::fprintf( stderr, "%s: Can't exec `%s': %s.\n",
+                        util_name, file_type.c_str(), std::strerror( errno ) );
+        _exit( 2 );
+        }
+      if( pid2 < 0 )
+        {
+        if( verbosity >= 0 )
+          std::fprintf( stderr, "%s: Can't fork `%s': %s.\n",
+                        util_name, file_type.c_str(), std::strerror( errno ) );
+        _exit( 2 );
+        }
+
+      if( close( fda[0] ) != 0 ||
+          !feed_data( infd, fda[1], magic_data, magic_size ) )
+        _exit( 2 );
+      if( close( fda[1] ) != 0 )
+        { show_error( "Can't close output of feeder", errno ); _exit( 2 ); }
+      _exit( wait_for_child( pid2, file_type.c_str() ) );
+      }
+					// parent
+    close( fda[0] ); close( fda[1] );
+    if( pid < 0 )
+      { show_error( "Can't fork decompressor feeder", errno ); return false; }
+    *pidp = pid;
+    }
+  else					// not compressed
+    {
+    const pid_t pid = fork();
+    if( pid == 0 )			// child (feeder)
+      {
+      const int outfd = open( fifoname.c_str(), O_WRONLY | o_binary );
+      if( outfd < 0 )
+        {
+        if( verbosity >= 0 )
+          std::fprintf( stderr, "%s: Can't open FIFO `%s' for writing: %s.\n",
+                      util_name, fifoname.c_str(), std::strerror( errno ) );
+        _exit( 2 );
+        }
+      if( !feed_data( infd, outfd, magic_data, magic_size ) )
+        _exit( 2 );
+      if( close( outfd ) != 0 )
+        { show_error( "Can't close output of feeder", errno ); _exit( 2 ); }
+      _exit( 0 );
+      }
+					// parent
+    if( pid < 0 )
+      { show_error( "Can't fork data feeder", errno ); return false; }
+    *pidp = pid;
+    }
+  return true;
+  }
+
+
+extern "C" void signal_handler( int sig ) throw()
+  {
+  remove_fifos();
+  std::signal( sig, SIG_DFL );
+  std::raise( sig );
+  }
+
+
+void set_signals() throw()
+  {
+  std::signal( SIGHUP, signal_handler );
+  std::signal( SIGINT, signal_handler );
+  std::signal( SIGTERM, signal_handler );
+  }
+
+} // end namespace
+
+
+int main( const int argc, const char * const argv[] )
+  {
+  std::vector< const char * > diff_args;	// args to diff, maybe empty
+  invocation_name = argv[0];
+  util_name = "zdiff";
+
+  const Arg_parser::Option options[] =
+    {
+    { 'a', "text",                   Arg_parser::no  },
+    { 'b', "ignore-space-change",    Arg_parser::no  },
+    { 'B', "ignore-blank-lines",     Arg_parser::no  },
+    { 'c',  0,                       Arg_parser::no  },
+    { 'C', "context",                Arg_parser::yes },
+    { 'd', "minimal",                Arg_parser::no  },
+    { 'E', "ignore-tab-expansion",   Arg_parser::no  },
+    { 'h', "help",                   Arg_parser::no  },
+    { 'i', "ignore-case",            Arg_parser::no  },
+    { 'p', "show-c-function",        Arg_parser::no  },
+    { 'q', "brief",                  Arg_parser::no  },
+    { 's', "report-identical-files", Arg_parser::no  },
+    { 't', "expand-tabs",            Arg_parser::no  },
+    { 'T', "initial-tab",            Arg_parser::no  },
+    { 'u',  0,                       Arg_parser::no  },
+    { 'U', "unified",                Arg_parser::yes },
+    { 'V', "version",                Arg_parser::no  },
+    { 'w', "ignore-all-space",       Arg_parser::no  },
+    {  0 ,  0,                       Arg_parser::no  } };
+
+  const Arg_parser parser( argc, argv, options );
+  if( parser.error().size() )				// bad option
+    { show_error( parser.error().c_str(), 0, true ); return 2; }
+
+  int argind = 0;
+  for( ; argind < parser.arguments(); ++argind )
+    {
+    const int code = parser.code( argind );
+    if( !code ) break;					// no more options
+    const char * const arg = parser.argument( argind ).c_str();
+    switch( code )
+      {
+      case 'a': diff_args.push_back( "-a" ); break;
+      case 'b': diff_args.push_back( "-b" ); break;
+      case 'B': diff_args.push_back( "-B" ); break;
+      case 'c': diff_args.push_back( "-c" ); break;
+      case 'C': diff_args.push_back( "-C" ); diff_args.push_back( arg ); break;
+      case 'd': diff_args.push_back( "-d" ); break;
+      case 'E': diff_args.push_back( "-E" ); break;
+      case 'h': show_help(); return 0;
+      case 'i': diff_args.push_back( "-i" ); break;
+      case 'p': diff_args.push_back( "-p" ); break;
+      case 'q': diff_args.push_back( "-q" ); break;
+      case 's': diff_args.push_back( "-s" ); break;
+      case 't': diff_args.push_back( "-t" ); break;
+      case 'T': diff_args.push_back( "-T" ); break;
+      case 'u': diff_args.push_back( "-u" ); break;
+      case 'U': diff_args.push_back( "-U" ); diff_args.push_back( arg ); break;
+      case 'V': show_version( "Zdiff" ); return 0;
+      case 'w': diff_args.push_back( "-w" ); break;
+      default : internal_error( "uncaught option" );
+      }
+    } // end process options
+
+#if defined(__MSVCRT__) || defined(__OS2__)
+  _setmode( STDIN_FILENO, O_BINARY );
+  _setmode( STDOUT_FILENO, O_BINARY );
+#endif
+
+  if( argind >= parser.arguments() )
+    { show_error( "No files given.", 0, true ); return 2; }
+  if( argind + 2 < parser.arguments() )
+    { show_error( "Too many files.", 0, true ); return 2; }
+
+  const int files = parser.arguments() - argind;
+  std::string filenames[2];		// file names of the two input files
+  filenames[0] = parser.argument( argind );
+  if( files == 2 ) filenames[1] = parser.argument( argind + 1 );
+
+  int infd[2];				// file descriptors of the two files
+  infd[0] = ( filenames[0] == "-" ) ?
+    STDIN_FILENO : open_instream( filenames[0] );
+  if( infd[0] < 0 ) return 2;
+
+  if( ( files == 1 && filenames[0] == "-" ) ||
+      ( files == 2 && check_identical( filenames[0].c_str(),
+                                       filenames[1].c_str() ) ) )
+    return 0;
+
+  if( files == 2 )
+    {
+    infd[1] = ( filenames[1] == "-" ) ?
+      STDIN_FILENO : open_instream( filenames[1] );
+    if( infd[1] < 0 ) return 2;
+    }
+  else
+    {
+    filenames[1] = filenames[0];
+    infd[1] = open_other_instream( filenames[1] );
+    if( infd[1] < 0 ) { infd[1] = STDIN_FILENO; filenames[1] = "-"; }
+    }
+
+  std::atexit( remove_fifos );
+  set_signals();
+  if( !set_fifonames( filenames ) ) return 2;
+
+  const pid_t diff_pid = fork();
+  if( diff_pid == 0 )			// child (diff)
+    {
+    const char ** const argv = new const char *[diff_args.size()+5];
+    argv[0] = "diff";
+    for( unsigned int i = 0; i < diff_args.size(); ++i )
+      argv[i+1] = diff_args[i];
+    argv[diff_args.size()+1] = "--";
+    argv[diff_args.size()+2] = fifonames[0].c_str();
+    argv[diff_args.size()+3] = fifonames[1].c_str();
+    argv[diff_args.size()+4] = 0;
+    execvp( argv[0], (char **)argv );
+    show_error( "Can't exec `diff'." );
+    _exit( 2 );
+    }
+					// parent
+  if( diff_pid < 0 )
+    { show_error( "Can't fork `diff'", errno ); return 2; }
+
+  pid_t pid[2];
+  if( !set_data_feeder( fifonames[0], infd[0], &pid[0] ) ||
+      !set_data_feeder( fifonames[1], infd[1], &pid[1] ) )
+    return 2;
+
+  int retval = wait_for_child( diff_pid, "diff" );
+
+  if( retval != 0 )
+    {
+    if( pid[0] ) kill( pid[0], SIGTERM );
+    if( pid[1] ) kill( pid[1], SIGTERM );
+    }
+  else
+    if( ( pid[0] && wait_for_child( pid[0], "data feeder" ) != 0 ) ||
+        ( pid[1] && wait_for_child( pid[1], "data feeder" ) != 0 ) )
+      retval = 2;
+
+  for( int i = 0; i < 2; ++i )
+    if( filenames[i] != "-" && close( infd[i] ) != 0 )
+      {
+      if( verbosity >= 0 )
+        std::fprintf( stderr, "%s: Can't close input file `%s': %s.\n",
+                      util_name, filenames[i].c_str(), std::strerror( errno ) );
+      retval = 2;
+      }
+
+  return retval;
+  }
diff --git a/zdiff.in b/zdiff.in
deleted file mode 100644
index dde93ba..0000000
--- a/zdiff.in
+++ /dev/null
@@ -1,160 +0,0 @@
-#! /bin/sh
-# Zdiff - Diff/cmp wrapper for compressed files.
-# Copyright (C) 2008, 2009 Antonio Diaz Diaz.
-#
-# This script is free software: you have unlimited permission
-# to copy, distribute and modify it.
-
-LC_ALL=C
-export LC_ALL
-args=
-diff_prog=diff
-file1=
-file2=
-two_hyphens=0
-
-# Loop over args
-while [ -n "$1" ] ; do
-
-	case "$1" in
-	--help | --he* | -h)
-		echo "Zdiff - Diff/cmp wrapper for compressed files."
-		echo
-		echo "Zdiff is a wrapper script around the diff and cmp commands that allows"
-		echo "transparent comparison of any combination of compressed and"
-		echo "non-compressed files. If any given file is compressed, its uncompressed"
-		echo "content is used. The supported compressors are bzip2, gzip, lzip and xz."
-		echo
-		echo "Zcmp is a shortcut for \"zdiff --cmp\""
-		echo
-		echo "Usage: $0 [OPTIONS] [DIFF_OPTIONS] FILE1 [FILE2]"
-		echo
-		echo "Compares FILE1 to FILE2. If FILE2 is omitted and FILE1 is compressed,"
-		echo "compares FILE1 to the file with the corresponding decompressed file"
-		echo "name (removes the extension from FILE1). If FILE2 is omitted and FILE1"
-		echo "is not compressed, compares FILE1 to the uncompressed contents of"
-		echo "FILE1.[bz2|gz|lz|xz] (the first one that is found)."
-		echo "DIFF_OPTIONS are passed directly to diff or cmp."
-		echo "The exit status from diff or cmp is preserved."
-		echo
-		echo "Options:"
-		echo "  -h, --help          display this help and exit"
-		echo "  -V, --version       output version information and exit"
-		echo "      --diff          use diff to compare files (default)"
-		echo "      --cmp           use cmp to compare files"
-		echo
-		echo "Report bugs to zutils-bug@nongnu.org"
-		echo "Zutils home page: http://www.nongnu.org/zutils/zutils.html"
-		exit 0 ;;
-	--version | --ve* | -V)
-		echo "Zdiff (zutils) VERSION"
-		echo "Copyright (C) 2009 Antonio Diaz Diaz."
-		echo "This script is free software: you have unlimited permission"
-		echo "to copy, distribute and modify it."
-		exit 0 ;;
-	--diff)
-		diff_prog=diff ;;
-	--cmp)
-		diff_prog=cmp ;;
-	-)
-		echo "$0: reading from stdin not supported"
-		exit 1 ;;
-	--)
-		shift; two_hyphens=1 ; break ;;
-	-?*)
-		args="${args} $1" ;;
-	*)
-		break ;;
-	esac
-	shift
-done
-
-# Loop over files
-for i in "$@" ; do
-	if [ "$i" = "--" ] && [ ${two_hyphens} = 0 ] ; then two_hyphens=1
-	else
-		if [ -f "$i" ] ; then
-			if [ -z "${file1}" ] ; then file1="$i"
-			else
-				if [ -z "${file2}" ] ; then file2="$i"
-				else
-					echo "$0: Too many files; use --help for usage." 1>&2
-				fi
-			fi
-		else
-			echo "$0: File \"$i\" not found or not a regular file" 1>&2
-			exit 1
-		fi
-	fi
-done
-
-if [ -z "${file1}" ] ; then
-	echo "$0: No files given; use --help for usage." 1>&2
-	exit 1
-fi
-
-if [ -z "${file2}" ] ; then
-	case "${file1}" in
-	*.bz2)	file2=`printf "%s" "${file1}" | sed -e 's,.bz2$,,'` ;;
-	*.tbz)	file2=`printf "%s" "${file1}" | sed -e 's,tbz$,tar,'` ;;
-	*.tbz2)	file2=`printf "%s" "${file1}" | sed -e 's,tbz2$,tar,'` ;;
-	*.gz)	file2=`printf "%s" "${file1}" | sed -e 's,.gz$,,'` ;;
-	*.tgz)	file2=`printf "%s" "${file1}" | sed -e 's,tgz$,tar,'` ;;
-	*.lz)	file2=`printf "%s" "${file1}" | sed -e 's,.lz$,,'` ;;
-	*.tlz)	file2=`printf "%s" "${file1}" | sed -e 's,tlz$,tar,'` ;;
-	*.xz)	file2=`printf "%s" "${file1}" | sed -e 's,.xz$,,'` ;;
-	*.txz)	file2=`printf "%s" "${file1}" | sed -e 's,txz$,tar,'` ;;
-	*)
-		if [ -f "${file1}.bz2" ] ;  then file2="${file1}.bz2"
-		elif [ -f "${file1}.gz" ] ; then file2="${file1}.gz"
-		elif [ -f "${file1}.lz" ] ; then file2="${file1}.lz"
-		elif [ -f "${file1}.xz" ] ; then file2="${file1}.xz"
-		else
-			echo "$0: Compressed version of ${file1} not found; use --help for usage." 1>&2
-			exit 1
-		fi ;;
-	esac
-fi
-
-prog1=
-prog2=
-bindir=`echo "$0" | sed -e 's,[^/]*$,,'`
-if [ -f "${file1}" ] ; then
-	prog_name=`"${bindir}"zutils -t -- "${file1}"`
-	case "${prog_name}" in
-	bzip2 | gzip | lzip | xz) prog1=${prog_name} ;;
-	esac
-fi
-if [ -f "${file2}" ] ; then
-	prog_name=`"${bindir}"zutils -t -- "${file2}"`
-	case "${prog_name}" in
-	bzip2 | gzip | lzip | xz) prog2=${prog_name} ;;
-	esac
-fi
-
-retval=0
-if [ -n "${prog1}" ] ; then
-	if [ -n "${prog2}" ] ; then
-		tmp_file=`mktemp "${TMPDIR:-/tmp}"/zdiff.XXXXXXXXXX` || {
-			echo 'cannot create a temporary file' 1>&2
-			exit 1
-		}
-		${prog2} -cdfq -- "${file2}" > "${tmp_file}" || exit 1
-		${prog1} -cdfq -- "${file1}" | ${diff_prog} ${args} - -- "${tmp_file}"
-		retval=$?
-		rm -f "${tmp_file}" || retval=$?
-	else
-		${prog1} -cdfq -- "${file1}" | ${diff_prog} ${args} - -- "${file2}"
-		retval=$?
-	fi
-else
-	if [ -n "${prog2}" ] ; then
-		${prog2} -cdfq -- "${file2}" | ${diff_prog} ${args} -- "${file1}" -
-		retval=$?
-	else
-		${diff_prog} ${args} -- "${file1}" "${file2}"
-		retval=$?
-	fi
-fi
-
-exit ${retval}
diff --git a/zegrep.in b/zegrep.in
index 0cac12e..e01f655 100644
--- a/zegrep.in
+++ b/zegrep.in
@@ -1,3 +1,3 @@
 #! /bin/sh
 bindir=`echo "$0" | sed -e 's,[^/]*$,,'`
-exec "${bindir}"zgrep -E "$@"
+exec "${bindir}"zutils --zgrep -E "$@"
diff --git a/zfgrep.in b/zfgrep.in
index c1a96d8..a3d54f3 100644
--- a/zfgrep.in
+++ b/zfgrep.in
@@ -1,3 +1,3 @@
 #! /bin/sh
 bindir=`echo "$0" | sed -e 's,[^/]*$,,'`
-exec "${bindir}"zgrep -F "$@"
+exec "${bindir}"zutils --zgrep -F "$@"
diff --git a/zgrep.cc b/zgrep.cc
new file mode 100644
index 0000000..b1c18b4
--- /dev/null
+++ b/zgrep.cc
@@ -0,0 +1,159 @@
+/*  Zgrep - search compressed files for a regular expression
+    Copyright (C) 2010 Antonio Diaz Diaz.
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+void show_zgrep_help() throw()
+  {
+  std::printf( "Zgrep is a front end to the grep program that allows transparent search\n" );
+  std::printf( "on any combination of compressed and non-compressed files. If any given\n" );
+  std::printf( "file is compressed, its uncompressed content is used. If a given file\n" );
+  std::printf( "does not exist, and its name does not end with one of the known\n" );
+  std::printf( "extensions, zgrep tries the compressed file names corresponding to the\n" );
+  std::printf( "supported compressors. If no files are specified, data is read from\n" );
+  std::printf( "standard input, decompressed if needed, and fed to grep. Data read from\n" );
+  std::printf( "standard input must be of the same type; all uncompressed or all\n" );
+  std::printf( "compressed with the same compressor.\n" );
+  std::printf( "The supported compressors are bzip2, gzip, lzip and xz.\n" );
+  std::printf( "\nUsage: zgrep [options] <pattern> [files]\n" );
+  std::printf( "\nExit status is 0 if match, 1 if no match, 2 if trouble.\n" );
+  std::printf( "\nOptions:\n" );
+  std::printf( "      --help                 display this help and exit\n" );
+  std::printf( "  -V, --version              output version information and exit\n" );
+  std::printf( "  -a, --text                 treat all files as text\n" );
+  std::printf( "  -A, --after-context=<n>    print <n> lines of trailing context\n" );
+  std::printf( "  -b, --byte-offset          print the byte offset of each line\n" );
+  std::printf( "  -B, --before-context=<n>   print <n> lines of leading context\n" );
+  std::printf( "  -c, --count                only print a count of matching lines per file\n" );
+  std::printf( "  -C, --context=<n>          print <n> lines of output context\n" );
+  std::printf( "  -e, --regexp=<pattern>     use <pattern> as the pattern to match\n" );
+  std::printf( "  -E, --extended-regexp      <pattern> is an extended regular expression\n" );
+  std::printf( "  -f, --file=<file>          obtain patterns from <file>\n" );
+  std::printf( "  -F, --fixed-strings        <pattern> is a set of newline-separated strings\n" );
+  std::printf( "  -h, --no-filename          suppress the prefixing filename on output\n" );
+  std::printf( "  -H, --with-filename        print the filename for each match\n" );
+  std::printf( "  -i, --ignore-case          ignore case distinctions\n" );
+  std::printf( "  -I                         ignore binary files\n" );
+  std::printf( "  -l, --files-with-matches   only print names of files containing matches\n" );
+  std::printf( "  -L, --files-without-match  only print names of files containing no matches\n" );
+  std::printf( "  -m, --max-count=<n>        stop after <n> matches\n" );
+  std::printf( "  -n, --line-number          print the line number of each line\n" );
+  std::printf( "  -o, --only-matching        show only the part of a line matching <pattern>\n" );
+  std::printf( "  -q, --quiet                suppress all messages\n" );
+  std::printf( "  -r, --recursive            operate recursively on directories\n" );
+  std::printf( "  -s, --no-messages          suppress error messages\n" );
+  std::printf( "  -v, --invert-match         select non-matching lines\n" );
+  std::printf( "      --verbose              verbose mode (show error messages)\n" );
+  std::printf( "  -w, --word-regexp          match only whole words\n" );
+  std::printf( "  -x, --line-regexp          match only whole lines\n" );
+  show_help_addr();
+  }
+
+
+int zgrep_stdin( int infd, const std::vector< const char * > & grep_args )
+  {
+  pid_t pid;
+  if( !set_data_feeder( &infd, &pid ) ) return 2;
+  const pid_t grep_pid = fork();
+  if( grep_pid == 0 )			// child (grep)
+    {
+    if( dup2( infd, STDIN_FILENO ) >= 0 && close( infd ) == 0 )
+      {
+      const char ** const argv = new const char *[grep_args.size()+2];
+      argv[0] = "grep";
+      for( unsigned int i = 0; i < grep_args.size(); ++i )
+        argv[i+1] = grep_args[i];
+      argv[grep_args.size()+1] = 0;
+      execvp( argv[0], (char **)argv );
+      }
+    show_error( "Can't exec `grep'." );
+    _exit( 2 );
+    }
+					// parent
+  if( grep_pid < 0 )
+    { show_error( "Can't fork `grep'", errno ); return 2; }
+  int retval = 0;
+  if( pid && wait_for_child( pid, "data feeder" ) != 0 ) retval = 2;
+  if( wait_for_child( grep_pid, "grep" ) != 0 ) retval = 2;
+  if( close( infd ) != 0 )
+    { show_error( "Can't close output of data feeder", errno ); return 2; }
+  return retval;
+  }
+
+
+int zgrep_file( int infd, const std::string & input_filename,
+                const std::vector< const char * > & grep_args,
+                const bool grep_list, const bool grep_show_name )
+  {
+  pid_t pid;
+  if( !set_data_feeder( &infd, &pid ) ) return 2;
+  int fda[2];				// pipe from grep
+  if( pipe( fda ) < 0 )
+    { show_error( "Can't create pipe", errno ); return 2; }
+  const pid_t grep_pid = fork();
+  if( grep_pid == 0 )			// child (grep)
+    {
+    if( dup2( infd, STDIN_FILENO ) >= 0 &&
+        dup2( fda[1], STDOUT_FILENO ) >= 0 &&
+        close( infd ) == 0 && close( fda[0] ) == 0 && close( fda[1] ) == 0 )
+      {
+      const char ** const argv = new const char *[grep_args.size()+2];
+      argv[0] = "grep";
+      for( unsigned int i = 0; i < grep_args.size(); ++i )
+        argv[i+1] = grep_args[i];
+      argv[grep_args.size()+1] = 0;
+      execvp( argv[0], (char **)argv );
+      }
+    show_error( "Can't exec `grep'." );
+    _exit( 2 );
+    }
+					// parent
+  close( fda[1] );
+  if( grep_pid < 0 )
+    { show_error( "Can't fork `grep'", errno ); return 2; }
+  enum { buffer_size = 256 };
+  uint8_t buffer[buffer_size];
+  bool line_begin = true;
+  while( true )
+    {
+    const int size = readblock( fda[0], buffer, buffer_size );
+    if( size != buffer_size && errno )
+      { show_error( "Read error", errno ); return 2; }
+    if( size > 0 && !grep_list )
+      {
+      if( grep_show_name )
+        for( int i = 0; i < size; ++i )
+          {
+          if( line_begin )
+            { line_begin = false; std::printf( "%s:", input_filename.c_str() ); }
+          if( buffer[i] == '\n' ) line_begin = true;
+          putchar( buffer[i] );
+          }
+      else if( std::fwrite( buffer, 1, size, stdout ) != (unsigned int)size )
+        { show_error( "Write error", errno ); return 2; }
+      }
+    if( size < buffer_size ) break;
+    }
+  int retval = 0;
+  if( pid && wait_for_child( pid, "data feeder" ) != 0 ) retval = 2;
+  if( wait_for_child( grep_pid, "grep" ) != 0 ) retval = 2;
+  if( grep_list && retval == 0 )
+    std::printf( "%s\n", input_filename.c_str() );
+  if( close( infd ) != 0 )
+    { show_error( "Can't close output of data feeder", errno ); return 2; }
+  if( close( fda[0] ) != 0 )
+    { show_error( "Can't close output of grep", errno ); return 2; }
+  return retval;
+  }
diff --git a/zgrep.in b/zgrep.in
index dbcb58c..bfbc490 100644
--- a/zgrep.in
+++ b/zgrep.in
@@ -1,136 +1,3 @@
 #! /bin/sh
-# Zgrep - Grep wrapper for compressed files.
-# Copyright (C) 2008, 2009 Antonio Diaz Diaz.
-#
-# This script is free software: you have unlimited permission
-# to copy, distribute and modify it.
-
-LC_ALL=C
-export LC_ALL
-args=
-have_pat=0
-list=0
-no_name=0
-two_hyphens=0
-
-# Loop over args until pattern is found
-while [ -n "$1" ] ; do
-
-	case "$1" in
-	--help | --he* | -h)
-		echo "Zgrep - Grep wrapper for compressed files."
-		echo
-		echo "Zgrep is a wrapper script around the grep command that allows"
-		echo "transparent search on any combination of compressed and non-compressed"
-		echo "files. If any given file is compressed, its uncompressed content is"
-		echo "used. If a given file does not exist, zgrep tries the compressed file"
-		echo "names corresponding to the supported compressors. If no files are"
-		echo "specified, data is read from standard input, decompressed if needed, and"
-		echo "fed to grep. Data read from standard input must be of the same type; all"
-		echo "uncompressed or all compressed with the same compressor."
-		echo "The supported compressors are bzip2, gzip, lzip and xz."
-		echo
-		echo "Zegrep is a shortcut for \"zgrep -E\""
-		echo "Zfgrep is a shortcut for \"zgrep -F\""
-		echo
-		echo "Usage: $0 [OPTIONS] [GREP_OPTIONS] PATTERN [FILES]"
-		echo
-		echo "GREP_OPTIONS are passed directly to grep."
-		echo "The exit status from grep is preserved."
-		echo
-		echo "Options:"
-		echo "  -h, --help          display this help and exit"
-		echo "  -V, --version       output version information and exit"
-		echo
-		echo "Report bugs to zutils-bug@nongnu.org"
-		echo "Zutils home page: http://www.nongnu.org/zutils/zutils.html"
-		exit 0 ;;
-	--version | --ve* | -V)
-		echo "Zgrep (zutils) VERSION"
-		echo "Copyright (C) 2009 Antonio Diaz Diaz."
-		echo "This script is free software: you have unlimited permission"
-		echo "to copy, distribute and modify it."
-		exit 0 ;;
-	-[drRzZ] | --di* | --exc* | --inc* | --nu* | --rec*)
-		echo "$0: option $1 not supported"
-		exit 1 ;;
-	-e?* | -f?* | --file=* | --reg*=*)
-		args="${args} $1"; have_pat=1 ;;
-	-e | -f | --file | --reg*)
-		args="${args} $1 $2"; shift; have_pat=1 ;;
-	--*=*)
-		args="${args} $1" ;;
-	-[ABCDm] | --af* | --be* | --binary-* | --con* | --de* | --[lm]a*)
-		args="${args} $1 $2"; shift ;;
-	-l | --files-with-*)
-		args="${args} $1"; list=1 ;;
-	-h | --no-f*)
-		args="${args} $1"; no_name=1 ;;
-	--)
-		shift ; two_hyphens=1 ; break ;;
-	-?*)
-		args="${args} $1" ;;
-	 *)
-	 	if [ ${have_pat} = 0 ] ; then args="${args} $1"; have_pat=1
-		else break
-		fi ;;
-	esac
-	shift
-done
-
-if [ ${have_pat} = 0 ] ; then
-	echo "$0: Pattern not found; use --help for usage." 1>&2
-	exit 1
-fi
-
-if [ $# = 0 ] ; then
-	bindir=`echo "$0" | sed -e 's,[^/]*$,,'`
-	prog_name=`"${bindir}"zutils -t`
-	case "${prog_name}" in
-	bzip2 | gzip | lzip | xz) prog="${prog_name} -cdfq" ;;
-	*)	prog=cat ;;
-	esac
-	{ "${bindir}"zutils -m ${prog_name} ; cat ; } | ${prog} | grep ${args}
-	exit $?
-fi
-
-retval=0
-for i in "$@" ; do
-	if [ "$i" = "--" ] && [ ${two_hyphens} = 0 ] ; then two_hyphens=1
-	else
-		if [ ! -f "$i" ] ; then
-			if [ -f "$i.gz" ] ;    then i="$i.gz"
-			elif [ -f "$i.bz2" ] ; then i="$i.bz2"
-			elif [ -f "$i.lz" ] ;  then i="$i.lz"
-			elif [ -f "$i.xz" ] ;  then i="$i.xz"
-			else
-				echo "$0: File \"$i\" not found or not a regular file" 1>&2
-				if [ ${retval} = 0 ] ; then retval=1 ; fi
-				continue
-			fi
-		fi
-		bindir=`echo "$0" | sed -e 's,[^/]*$,,'`
-		prog_name=`"${bindir}"zutils -t -- "$i"`
-		case "${prog_name}" in
-		bzip2 | gzip | lzip | xz) prog="${prog_name} -cdfq" ;;
-		*)	prog=cat ;;
-		esac
-		if [ ${list} = 1 ] ; then
-			${prog} -- "$i" | grep ${args} 2>&1 > /dev/null && echo "$i"
-			r=$?
-		elif [ $# = 1 ] || [ ${no_name} = 1 ] ; then
-			${prog} -- "$i" | grep ${args}
-			r=$?
-		else
-			j=`printf "%s" "$i" | sed -e 's,\\\\,\\\\\\\\,g'`
-			j=`printf "%s" "$j" | sed -e 's,|,\\\\|,g'`
-			j=`printf "%s" "$j" | sed -e 's,&,\\\\&,g'`
-			j=`printf "%s" "$j" | tr '\n' ' '`
-			${prog} -- "$i" | grep ${args} | sed -e "s,^,${j}:,"
-			r=$?
-		fi
-		[ $r != 0 ] && retval="$r"
-	fi
-done
-
-exit ${retval}
+bindir=`echo "$0" | sed -e 's,[^/]*$,,'`
+exec "${bindir}"zutils --zgrep "$@"
diff --git a/ztest.cc b/ztest.cc
new file mode 100644
index 0000000..6a9b910
--- /dev/null
+++ b/ztest.cc
@@ -0,0 +1,119 @@
+/*  Ztest - verify integrity of compressed files
+    Copyright (C) 2010 Antonio Diaz Diaz.
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+void show_ztest_help() throw()
+  {
+  std::printf( "Ztest verifies the integrity of the specified compressed files.\n" );
+  std::printf( "Non-compressed files are ignored. If no files are specified, the\n" );
+  std::printf( "integrity of compressed data read from standard input is verified. Data\n" );
+  std::printf( "read from standard input must be all compressed with the same compressor.\n" );
+  std::printf( "The supported compressors are bzip2, gzip, lzip and xz.\n" );
+  std::printf( "\nUsage: ztest [options] [files]\n" );
+  std::printf( "\nExit status is 2 if any compressed file is corrupt, 0 otherwise.\n" );
+  std::printf( "\nOptions:\n" );
+  std::printf( "  -h, --help                 display this help and exit\n" );
+  std::printf( "  -V, --version              output version information and exit\n" );
+  std::printf( "  -q, --quiet                suppress all messages\n" );
+  std::printf( "  -r, --recursive            operate recursively on directories\n" );
+  std::printf( "  -v, --verbose              be verbose (a 2nd -v gives more)\n" );
+  show_help_addr();
+  }
+
+
+int ztest_stdin( const int infd,
+                 const std::vector< const char * > & ztest_args )
+  {
+  std::string file_type;
+  const uint8_t * magic_data;
+  int magic_size = 0;
+  if( !test_format( infd, file_type, &magic_data, &magic_size ) )
+    { show_error( "Unknown data format read from stdin." ); return 2; }
+  int fda[2];
+  if( pipe( fda ) < 0 )
+    { show_error( "Can't create pipe", errno ); return 1; }
+  const pid_t pid = fork();
+
+  if( pid == 0 )			// child (decompressor)
+    {
+    if( dup2( fda[0], STDIN_FILENO ) >= 0 &&
+        close( fda[0] ) == 0 && close( fda[1] ) == 0 )
+      {
+      const char ** const argv = new const char *[ztest_args.size()+3];
+      argv[0] = file_type.c_str();
+      for( unsigned int i = 0; i < ztest_args.size(); ++i )
+        argv[i+1] = ztest_args[i];
+      argv[ztest_args.size()+1] = "-t";
+      argv[ztest_args.size()+2] = 0;
+      execvp( argv[0], (char **)argv );
+      }
+    if( verbosity >= 0 )
+      std::fprintf( stderr, "%s: Can't exec `%s': %s.\n",
+                    util_name, file_type.c_str(), std::strerror( errno ) );
+    _exit( 1 );
+    }
+					// parent
+  if( pid < 0 )
+    {
+    if( verbosity >= 0 )
+      std::fprintf( stderr, "%s: Can't fork `%s': %s.\n",
+                    util_name, file_type.c_str(), std::strerror( errno ) );
+    return 1;
+    }
+  close( fda[0] );
+  if( !feed_data( infd, fda[1], magic_data, magic_size ) ) return 1;
+  if( close( fda[1] ) != 0 )
+    { show_error( "Can't close output of data feeder", errno ); return 1; }
+  return wait_for_child( pid, file_type.c_str() );
+  }
+
+
+int ztest_file( const int infd, const std::string & input_filename,
+                const std::vector< const char * > & ztest_args )
+  {
+  std::string file_type;
+  const uint8_t * magic_data;
+  int magic_size = 0;
+  if( !test_format( infd, file_type, &magic_data, &magic_size ) )
+    return 0;				// ignored
+  const pid_t pid = fork();
+
+  if( pid == 0 )			// child (decompressor)
+    {
+    const char ** const argv = new const char *[ztest_args.size()+5];
+    argv[0] = file_type.c_str();
+    for( unsigned int i = 0; i < ztest_args.size(); ++i )
+      argv[i+1] = ztest_args[i];
+    argv[ztest_args.size()+1] = "-t";
+    argv[ztest_args.size()+2] = "--";
+    argv[ztest_args.size()+3] = input_filename.c_str();
+    argv[ztest_args.size()+4] = 0;
+    execvp( argv[0], (char **)argv );
+    if( verbosity >= 0 )
+      std::fprintf( stderr, "%s: Can't exec `%s': %s.\n",
+                    util_name, argv[0], std::strerror( errno ) );
+    _exit( 1 );
+    }
+					// parent
+  if( pid < 0 )
+    {
+    if( verbosity >= 0 )
+      std::fprintf( stderr, "%s: Can't fork `%s': %s.\n",
+                    util_name, file_type.c_str(), std::strerror( errno ) );
+    return 1;
+    }
+  return wait_for_child( pid, file_type.c_str() );
+  }
diff --git a/ztest.in b/ztest.in
index 98e93f6..cc7dc9b 100644
--- a/ztest.in
+++ b/ztest.in
@@ -1,102 +1,3 @@
 #! /bin/sh
-# Ztest - Test integrity of compressed files.
-# Copyright (C) 2009 Antonio Diaz Diaz.
-#
-# This script is free software: you have unlimited permission
-# to copy, distribute and modify it.
-
-LC_ALL=C
-export LC_ALL
-args=
-recursive=0
-two_hyphens=0
-
-# Loop over args until a filename is found
-while [ -n "$1" ] ; do
-
-	case "$1" in
-	--help | --he* | -h)
-		echo "Ztest - Test integrity of compressed files."
-		echo
-		echo "Ztest verifies the integrity of the specified compressed files."
-		echo "Non-compressed files are ignored. If no files are specified, the"
-		echo "integrity of compressed data read from standard input is verified. Data"
-		echo "read from standard input must be all compressed with the same compressor."
-		echo "The supported compressors are bzip2, gzip, lzip and xz."
-		echo
-		echo "Usage: $0 [OPTIONS] [FILES]"
-		echo
-		echo "The exit status is 1 if any compressed file is corrupt, 0 otherwise."
-		echo
-		echo "Options:"
-		echo "  -h, --help          display this help and exit"
-		echo "  -V, --version       output version information and exit"
-		echo "  -q, --quiet         suppress all messages"
-		echo "  -r, --recursive     operate recursively on directories"
-		echo "  -v, --verbose       be verbose (a 2nd -v gives more)"
-		echo
-		echo "Report bugs to zutils-bug@nongnu.org"
-		echo "Zutils home page: http://www.nongnu.org/zutils/zutils.html"
-		exit 0 ;;
-	--version | --ve* | -V)
-		echo "Ztest (zutils) VERSION"
-		echo "Copyright (C) 2009 Antonio Diaz Diaz."
-		echo "This script is free software: you have unlimited permission"
-		echo "to copy, distribute and modify it."
-		exit 0 ;;
-	-r | --re*)
-		recursive=1 ;;
-	-v | -vv | -vvv | --ve* | -q | --qu*)
-		args="${args} $1" ;;
-	--)
-		shift ; two_hyphens=1 ; break ;;
-	- | -?*)
-		;;
-	 *)
-		break ;;
-	esac
-	shift
-done
-
-if [ $# = 0 ] ; then
-	bindir=`echo "$0" | sed -e 's,[^/]*$,,'`
-	prog=`"${bindir}"zutils -t`
-	case "${prog}" in
-	bzip2 | gzip | lzip | xz)
-		;;
-	*)	echo "$0: Unknown data format read from stdin" 1>&2
-		exit 1 ;;
-	esac
-	{ "${bindir}"zutils -m ${prog} ; cat ; } | ${prog} -t ${args}
-	exit $?
-fi
-
-retval=0
-for i in "$@" ; do
-	if [ "$i" = "--" ] && [ ${two_hyphens} = 0 ] ; then two_hyphens=1
-	else
-		if [ ! -f "$i" ] ; then
-			if [ ${recursive} = 1 ] && [ -d "$i" ] ; then
-				bad_files=`find "$i" -type f \( -exec "$0" ${args} '{}' ';' -o -print \)`
-				if [ ${retval} = 0 ] && [ -n "${bad_files}" ] ; then retval=1 ; fi
-				continue
-			else
-				echo "$0: File \"$i\" not found or not a regular file" 1>&2
-				if [ ${retval} = 0 ] ; then retval=1 ; fi
-				continue
-			fi
-		fi
-		bindir=`echo "$0" | sed -e 's,[^/]*$,,'`
-		prog=`"${bindir}"zutils -t -- "$i"`
-		case "${prog}" in
-		bzip2 | gzip | lzip | xz)
-			;;
-		*)	continue ;;
-		esac
-		${prog} -t ${args} -- "$i"
-		r=$?
-		if [ $r != 0 ] ; then retval=$r ; fi
-	fi
-done
-
-exit ${retval}
+bindir=`echo "$0" | sed -e 's,[^/]*$,,'`
+exec "${bindir}"zutils --ztest "$@"
diff --git a/zutils.cc b/zutils.cc
new file mode 100644
index 0000000..5451534
--- /dev/null
+++ b/zutils.cc
@@ -0,0 +1,301 @@
+/*  Zutils - Utilities dealing with compressed files
+    Copyright (C) 2009, 2010 Antonio Diaz Diaz.
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#define _FILE_OFFSET_BITS 64
+
+#include <cerrno>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <string>
+#include <stdint.h>
+#include <unistd.h>
+#include <sys/wait.h>
+
+#include "zutils.h"
+
+
+const char * invocation_name = 0;
+const char * util_name = program_name;
+
+int verbosity = 0;
+
+
+// Returns the number of bytes really read.
+// If (returned value < size) and (errno == 0), means EOF was reached.
+//
+int readblock( const int fd, uint8_t * const buf, const int size ) throw()
+  {
+  int rest = size;
+  errno = 0;
+  while( rest > 0 )
+    {
+    errno = 0;
+    const int n = read( fd, buf + size - rest, rest );
+    if( n > 0 ) rest -= n;
+    else if( n == 0 ) break;
+    else if( errno != EINTR && errno != EAGAIN ) break;
+    }
+  return ( rest > 0 ) ? size - rest : size;
+  }
+
+
+// Returns the number of bytes really written.
+// If (returned value < size), it is always an error.
+//
+int writeblock( const int fd, const uint8_t * const buf, const int size ) throw()
+  {
+  int rest = size;
+  errno = 0;
+  while( rest > 0 )
+    {
+    errno = 0;
+    const int n = write( fd, buf + size - rest, rest );
+    if( n > 0 ) rest -= n;
+    else if( errno && errno != EINTR && errno != EAGAIN ) break;
+    }
+  return ( rest > 0 ) ? size - rest : size;
+  }
+
+
+bool feed_data( const int infd, const int outfd,
+                const uint8_t * magic_data, const int magic_size )
+  {
+  if( writeblock( outfd, magic_data, magic_size ) != magic_size )
+    { show_error( "Write error", errno ); return false; }
+  enum { buffer_size = 4096 };
+  uint8_t buffer[buffer_size];
+  while( true )
+    {
+    const int size = readblock( infd, buffer, buffer_size );
+    if( size != buffer_size && errno )
+      { show_error( "Read error", errno ); return false; }
+    if( size > 0 && writeblock( outfd, buffer, size ) != size )
+      { show_error( "Write error", errno ); return false; }
+    if( size < buffer_size ) break;
+    }
+  return true;
+  }
+
+
+bool set_data_feeder( int * const infdp, pid_t * const pidp )
+  {
+  std::string file_type;
+  const uint8_t * magic_data;
+  int magic_size;
+  const bool compressed =
+    test_format( *infdp, file_type, &magic_data, &magic_size );
+
+  if( compressed )			// compressed with `file_type'
+    {
+    int fda[2];				// pipe from feeder
+    int fda2[2];			// pipe from decompressor
+    if( pipe( fda ) < 0 || pipe( fda2 ) < 0 )
+      { show_error( "Can't create pipe", errno ); return false; }
+    const int old_infd = *infdp;
+    *infdp = fda2[0];
+    const pid_t pid = fork();
+    if( pid == 0 )			// child (decompressor feeder)
+      {
+      const pid_t pid2 = fork();
+      if( pid2 == 0 )			// grandchild (decompressor)
+        {
+        if( dup2( fda[0], STDIN_FILENO ) >= 0 &&
+            dup2( fda2[1], STDOUT_FILENO ) >= 0 &&
+            close( fda[0] ) == 0 && close( fda[1] ) == 0 &&
+            close( fda2[0] ) == 0 && close( fda2[1] ) == 0 )
+          execlp( file_type.c_str(), file_type.c_str(), "-cdfq", (char *)0 );
+        if( verbosity >= 0 )
+          std::fprintf( stderr, "%s: Can't exec `%s': %s.\n",
+                        util_name, file_type.c_str(), std::strerror( errno ) );
+        _exit( 2 );
+        }
+      if( pid2 < 0 )
+        {
+        if( verbosity >= 0 )
+          std::fprintf( stderr, "%s: Can't fork `%s': %s.\n",
+                        util_name, file_type.c_str(), std::strerror( errno ) );
+        _exit( 2 );
+        }
+
+      if( close( fda[0] ) != 0 ||
+          close( fda2[0] ) != 0 || close( fda2[1] ) != 0 ||
+          !feed_data( old_infd, fda[1], magic_data, magic_size ) )
+        _exit( 2 );
+      if( close( fda[1] ) != 0 )
+        { show_error( "Can't close output of decompressor feeder", errno );
+          _exit( 2 ); }
+      _exit( wait_for_child( pid2, file_type.c_str() ) );
+      }
+					// parent
+    close( fda[0] ); close( fda[1] ); close( fda2[1] );
+    if( pid < 0 )
+      { show_error( "Can't fork decompressor feeder", errno ); return false; }
+    *pidp = pid;
+    }
+  else					// not compressed
+    {
+    int fda[2];				// pipe from feeder
+    if( pipe( fda ) < 0 )
+      { show_error( "Can't create pipe", errno ); return false; }
+    const int old_infd = *infdp;
+    *infdp = fda[0];
+    const pid_t pid = fork();
+    if( pid == 0 )			// child (feeder)
+      {
+      if( close( fda[0] ) != 0 ||
+          !feed_data( old_infd, fda[1], magic_data, magic_size ) )
+        _exit( 2 );
+      if( close( fda[1] ) != 0 )
+        { show_error( "Can't close output of data feeder", errno );
+          _exit( 2 ); }
+      _exit( 0 );
+      }
+					// parent
+    close( fda[1] );
+    if( pid < 0 )
+      { show_error( "Can't fork data feeder", errno ); return false; }
+    *pidp = pid;
+    }
+  return true;
+  }
+
+
+void show_help_addr() throw()
+  {
+  std::printf( "\nReport bugs to zutils-bug@nongnu.org\n" );
+  std::printf( "Zutils home page: http://www.nongnu.org/zutils/zutils.html\n" );
+  }
+
+
+void show_version( const char * const Util_name ) throw()
+  {
+  if( !Util_name || !*Util_name )
+    std::printf( "%s %s\n", Program_name, PROGVERSION );
+  else
+    std::printf( "%s (%s) %s\n", Util_name, program_name, PROGVERSION );
+  std::printf( "Copyright (C) %s Antonio Diaz Diaz.\n", program_year );
+  std::printf( "License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>\n" );
+  std::printf( "This is free software: you are free to change and redistribute it.\n" );
+  std::printf( "There is NO WARRANTY, to the extent permitted by law.\n" );
+  }
+
+
+void show_error( const char * const msg, const int errcode,
+                 const bool help ) throw()
+  {
+  if( verbosity >= 0 )
+    {
+    if( msg && msg[0] )
+      {
+      std::fprintf( stderr, "%s: %s", util_name, msg );
+      if( errcode > 0 )
+        std::fprintf( stderr, ": %s", std::strerror( errcode ) );
+      std::fprintf( stderr, "\n" );
+      }
+    if( help && invocation_name && invocation_name[0] )
+      std::fprintf( stderr, "Try `%s --help' for more information.\n",
+                    invocation_name );
+    }
+  }
+
+
+void internal_error( const char * const msg )
+  {
+  if( verbosity >= 0 )
+    std::fprintf( stderr, "%s: internal error: %s.\n", util_name, msg );
+  std::exit( 3 );
+  }
+
+
+unsigned char xdigit( const int value ) throw()
+  {
+  if( value >= 0 && value <= 9 ) return '0' + value;
+  if( value >= 10 && value <= 15 ) return 'A' + ( value - 10 );
+  return 0;
+  }
+
+
+bool test_format( const int infd, std::string & file_type,
+                  const uint8_t ** const magic_datap, int * const magic_sizep )
+  {
+  enum { buf_size = 5 };
+  static uint8_t buf[buf_size];
+  int i = 0;
+  file_type.clear();
+  if( readblock( infd, buf, 1 ) == 1 )
+    {
+    ++i;
+    if( buf[0] == bzip2_magic[0] )
+      {
+      if( readblock( infd, &buf[i], 1 ) == 1 && buf[i++] == bzip2_magic[1] &&
+          readblock( infd, &buf[i], 1 ) == 1 && buf[i++] == bzip2_magic[2] )
+        { file_type = "bzip2";
+          *magic_datap = bzip2_magic; *magic_sizep = bzip2_magic_size; }
+      }
+    else if( buf[0] == gzip_magic[0] )
+      {
+      if( readblock( infd, &buf[i], 1 ) == 1 && buf[i++] == gzip_magic[1] )
+        { file_type = "gzip";
+          *magic_datap = gzip_magic; *magic_sizep = gzip_magic_size; }
+      }
+    else if( buf[0] == lzip_magic[0] )
+      {
+      if( readblock( infd, &buf[i], 1 ) == 1 && buf[i++] == lzip_magic[1] &&
+          readblock( infd, &buf[i], 1 ) == 1 && buf[i++] == lzip_magic[2] &&
+          readblock( infd, &buf[i], 1 ) == 1 && buf[i++] == lzip_magic[3] )
+        { file_type = "lzip";
+          *magic_datap = lzip_magic; *magic_sizep = lzip_magic_size; }
+      }
+    else if( buf[0] == xz_magic[0] )
+      {
+      if( readblock( infd, &buf[i], 1 ) == 1 && buf[i++] == xz_magic[1] &&
+          readblock( infd, &buf[i], 1 ) == 1 && buf[i++] == xz_magic[2] &&
+          readblock( infd, &buf[i], 1 ) == 1 && buf[i++] == xz_magic[3] &&
+          readblock( infd, &buf[i], 1 ) == 1 && buf[i++] == xz_magic[4] )
+        { file_type = "xz";
+          *magic_datap = xz_magic; *magic_sizep = xz_magic_size; }
+      }
+    }
+  if( file_type.size() ) return true;
+  for( int j = 0; j < i; ++j )
+    {
+    file_type += xdigit( buf[j] >> 4 );
+    file_type += xdigit( buf[j] & 0x0F );
+    }
+  *magic_datap = buf; *magic_sizep = i;
+  return false;
+  }
+
+
+int wait_for_child( const pid_t pid, const char * const name )
+  {
+  int status;
+  while( waitpid( pid, &status, 0 ) == -1 )
+    {
+    if( errno != EINTR )
+      {
+      if( verbosity >= 0 )
+        std::fprintf( stderr, "%s: Error waiting termination of `%s': %s.\n",
+                  util_name, name, std::strerror( errno ) );
+      _exit( 1 );
+      }
+    }
+
+  if( WIFEXITED( status ) ) return WEXITSTATUS( status );
+  else return 1;
+  }
diff --git a/zutils.h b/zutils.h
new file mode 100644
index 0000000..296f3ac
--- /dev/null
+++ b/zutils.h
@@ -0,0 +1,53 @@
+/*  Zutils - Utilities dealing with compressed files
+    Copyright (C) 2009, 2010 Antonio Diaz Diaz.
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+const char * const Program_name = "Zutils";
+const char * const program_name = "zutils";
+const char * const program_year = "2010";
+extern const char * invocation_name;
+extern const char * util_name;
+
+extern int verbosity;
+
+const char * const simple_extensions[] = { ".gz", ".lz", ".bz2", ".xz", 0 };
+
+enum { bzip2_magic_size = 3 };
+enum {  gzip_magic_size = 2 };
+enum {  lzip_magic_size = 4 };
+enum {    xz_magic_size = 5 };
+const uint8_t bzip2_magic[bzip2_magic_size] = { 'B', 'Z', 'h' };
+const uint8_t  gzip_magic[ gzip_magic_size] = { '\x1F', '\x8B' };
+const uint8_t  lzip_magic[ lzip_magic_size] = { 'L', 'Z', 'I', 'P' };
+const uint8_t    xz_magic[   xz_magic_size] = { '\xFD', '7', 'z', 'X', 'Z' };
+
+
+int readblock( const int fd, uint8_t * const buf, const int size ) throw();
+int writeblock( const int fd, const uint8_t * const buf, const int size ) throw();
+bool feed_data( const int infd, const int outfd,
+                const uint8_t * magic_data, const int magic_size );
+bool set_data_feeder( int * const infdp, pid_t * const pidp );
+
+void show_help_addr() throw();
+void show_version( const char * const Util_name = 0 ) throw();
+void show_error( const char * const msg, const int errcode = 0,
+                 const bool help = false ) throw();
+void internal_error( const char * const msg );
+
+bool test_format( const int infd, std::string & file_type,
+                  const uint8_t ** magic_data, int * magic_sizep );
+
+int wait_for_child( const pid_t pid, const char * const name );