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+Description
+
+Zutils is a collection of utilities able to process any combination of
+compressed and uncompressed files transparently. If any file given,
+including standard input, is compressed, its decompressed content is used.
+Compressed files are decompressed on the fly; no temporary files are
+created. Data format is detected by its identifier string (magic bytes), not
+by the file name extension. Empty files are considered uncompressed.
+
+These utilities are not wrapper scripts but safer and more efficient C++
+programs. In particular the option '--recursive' is very efficient in
+those utilities supporting it.
+
+The utilities provided are zcat, zcmp, zdiff, zgrep, ztest, and zupdate.
+The formats supported are bzip2, gzip, lzip, xz, and zstd.
+Zutils uses external compressors. The compressor to be used for each format
+is configurable at runtime.
+
+zcat, zcmp, zdiff, and zgrep are improved replacements for the shell scripts
+provided by GNU gzip. ztest is unique to zutils. zupdate is similar to
+gzip's znew.
+
+NOTE: Bzip2 and lzip provide well-defined values of exit status, which makes
+them safe to use with zutils. Gzip and xz may return ambiguous warning
+values, making them less reliable back ends for zutils. Zstd currently does
+not even document its exit status in its man page.
+
+FORMAT NOTE 1: The option '--format' allows the processing of a subset
+of formats in recursive mode and when trying compressed file names. For
+example, use the following command to search for the string 'foo' in
+gzip and lzip files only:
+'zgrep foo -r --format=gz,lz somedir somefile.tar'.
+
+FORMAT NOTE 2: The standard POSIX compress format (.Z) is obsolete and is
+only supported through gzip. For this to work, the gzip program used (for
+example GNU gzip) must be able to decompress .Z files.
+
+LANGUAGE NOTE: Uncompressed = not compressed = plain data; it may never have
+been compressed. Decompressed is used to refer to data which have undergone
+the process of decompression.
+
+
+Copyright (C) 2009-2024 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 configure itself.