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diff --git a/doc/zutils.texinfo b/doc/zutils.texinfo index ea635ba..5bbc692 100644 --- a/doc/zutils.texinfo +++ b/doc/zutils.texinfo @@ -6,8 +6,8 @@ @finalout @c %**end of header -@set UPDATED 2 August 2013 -@set VERSION 1.1 +@set UPDATED 4 September 2013 +@set VERSION 1.2-pre2 @dircategory Data Compression @direntry @@ -43,13 +43,13 @@ This manual is for Zutils (version @value{VERSION}, @value{UPDATED}). * Zdiff:: Comparing compressed files line by line * Zgrep:: Searching inside compressed files * Ztest:: Testing integrity of compressed files +* Zupdate:: Recompressing files to lzip format * Problems:: Reporting bugs * Concept index:: Index of concepts @end menu @sp 1 -Copyright @copyright{} 2008, 2009, 2010, 2011, 2012, 2013 -Antonio Diaz Diaz. +Copyright @copyright{} 2009, 2010, 2011, 2012, 2013 Antonio Diaz Diaz. This manual is free documentation: you have unlimited permission to copy, distribute and modify it. @@ -70,12 +70,13 @@ programs. In particular the @samp{--recursive} option is very efficient in those utilities supporting it. @noindent -The provided utilities are zcat, zcmp, zdiff, zgrep and ztest.@* +The provided utilities are zcat, zcmp, zdiff, zgrep, ztest and zupdate.@* The supported formats are bzip2, gzip, lzip and xz.@* 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 with GNU gzip. Ztest is unique to zutils. +scripts provided with 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 @@ -638,14 +639,85 @@ Operate recursively on directories. @item -v @itemx --verbose -Verbose mode. Show the verify status for each file processed. +Verbose mode. Show the verify status for each file processed.@* Further -v's increase the verbosity level. @end table +@node Zupdate +@chapter Zupdate +@cindex zupdate + +Zupdate recompresses files from bzip2, gzip, and xz formats to lzip +format. The originals are compared with the new files and then deleted. +Only regular files with standard file name extensions are recompressed, +other files are ignored. Compressed files are decompressed and then +recompressed on the fly; no temporary files are created. The lzip format +is chosen as destination because it is by far the most appropriate for +long-term data archiving. + +If the lzip compressed version of a file already exists, the file is +skipped unless the @samp{--force} option is given. In this case, if the +comparison fails, an error is returned and the original file is not +deleted. The operation of zupdate is meant to be safe and not produce +any data loss. Therefore, existing lzip compressed files are never +overwritten nor deleted. + +The names of the original files must have one of the following +extensions: @samp{.bz2}, @samp{.tbz}, @samp{.tbz2}, @samp{.gz}, +@samp{.tgz}, @samp{.xz}, @samp{.txz}. The files produced have the +extensions @samp{.lz} or @samp{.tar.lz}. + +The format for running zupdate is: + +@example +zupdate [@var{options}] [@var{files}] +@end example + +@noindent +Exit status is 0 if all the compressed files were successfully +recompressed (if needed), compared and deleted. Non-zero otherwise. + +Zupdate supports the following options: + +@table @samp +@item -f +@itemx --force +Do not skip a file for which a lzip compressed version already exists. +@samp{--force} compares the content of the input file with the content +of the lzip file and deletes the input file if both contents are +identical. + +@item -l +@itemx --lzip-verbose +Pass a @samp{-v} option to the lzip compressor so that it shows the +compression ratio for each file processed. Using lzip 1.15 and newer, a +second @samp{-l} shows the progress of compression. Use it together with +@samp{-v} to see the name of the file. + +@item -q +@itemx --quiet +Quiet operation. Suppress all messages. + +@item -r +@itemx --recursive +Operate recursively on directories. + +@item -v +@itemx --verbose +Verbose mode. Show the files being processed. A second @samp{-v} also +shows the files being ignored. + +@item -0 .. -9 +Set the compression level of lzip. By default zupdate passes @samp{-9} +to lzip. + +@end table + + @node Problems -@chapter Reporting Bugs +@chapter Reporting bugs @cindex bugs @cindex getting help |