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Diffstat (limited to 'doc/zutils.texi')
| -rw-r--r-- | doc/zutils.texi | 57 |
1 files changed, 31 insertions, 26 deletions
diff --git a/doc/zutils.texi b/doc/zutils.texi index 236265c..34c15b4 100644 --- a/doc/zutils.texi +++ b/doc/zutils.texi @@ -6,8 +6,8 @@ @finalout @c %**end of header -@set UPDATED 29 May 2015 -@set VERSION 1.4 +@set UPDATED 15 May 2016 +@set VERSION 1.5 @dircategory Data Compression @direntry @@ -49,7 +49,7 @@ This manual is for Zutils (version @value{VERSION}, @value{UPDATED}). @end menu @sp 1 -Copyright @copyright{} 2009-2015 Antonio Diaz Diaz. +Copyright @copyright{} 2009-2016 Antonio Diaz Diaz. This manual is free documentation: you have unlimited permission to copy, distribute and modify it. @@ -72,7 +72,8 @@ in those utilities supporting it. @noindent 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. +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 @@ -164,7 +165,7 @@ Don't read the runtime configuration file @samp{zutilsrc}. @itemx --lz=@var{command} @itemx --xz=@var{command} Set program (may include arguments) to be used as (de)compressor for the -given format. The mane of the program can't begin with @samp{-}. These +given format. The name of the program can't begin with @samp{-}. These options override the values set in @file{zutilsrc}. The compression program used must meet three requirements: @@ -189,7 +190,7 @@ It must return 0 if no errors occurred, and a non-zero value otherwise. @file{zutilsrc} is the runtime configuration file for zutils. In it you may define the compressor name and options to be used for each format. -The @file{zutilsrc} file is optional; you do not need to install it in +The @file{zutilsrc} file is optional; you don't need to install it in order to run zutils. The compressors specified in the command line override those specified @@ -217,16 +218,15 @@ where <format> is one of @samp{bz2}, @samp{gz}, @samp{lz} or @samp{xz}. @chapter Zcat @cindex zcat -zcat copies each given file (@samp{-} means standard input), to standard -output. If any given file is compressed, its decompressed 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 formats. +zcat copies each given file to standard output. If any given file is +compressed, its decompressed 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 formats. -If no files are specified, data is read from standard input, -decompressed if needed, and sent to standard output. Data read from -standard input must be of the same type; all uncompressed or all in the -same compression format. +If no files are specified, or if a file is specified as @samp{-}, data +is read from standard input, decompressed if needed, and sent to +standard output. Data read from standard input must be of the same type; +all uncompressed or all in the same compression format. The format for running zcat is: @@ -378,7 +378,7 @@ without verifying its format, and the exact file names of both @itemx -s @itemx --quiet @itemx --silent -Do not print anything; only return an exit status indicating whether the +Don't print anything; only return an exit status indicating whether the files differ. @end table @@ -510,10 +510,10 @@ 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 formats. -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 in the same -compression format. +If no files are specified, or if a file is specified as @samp{-}, 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 in the same compression format. The format for running zgrep is: @@ -562,7 +562,11 @@ Treat @var{pattern} as an extended regular expression. @item -f @var{file} @itemx --file=@var{file} -Obtain patterns from @var{file}, one per line. +Obtain patterns from @var{file}, one per line.@* +When searching in several files at once, command substitution can be +used with @code{-e} to read @var{file} only once, for example if +@var{file} is not a regular file: +@w{@code{zgrep -e "$(cat @var{file})" file1.lz file2.gz}} @item -F @itemx --fixed-strings @@ -648,9 +652,10 @@ Match only whole lines. @cindex ztest ztest verifies the integrity of the specified compressed files. -Uncompressed 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 in the same compression format. +Uncompressed files are ignored. If no files are specified, or if a file +is specified as @samp{-}, the integrity of compressed data read from +standard input is verified. Data read from standard input must be all in +the same compression format. Note that some xz files lack integrity information, and therefore can't be verified as reliably as the other formats can. @@ -700,7 +705,7 @@ Further -v's increase the verbosity level. @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. +format. Each original is compared with the new file 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 @@ -745,7 +750,7 @@ zupdate supports the following options: @table @code @item -f @itemx --force -Do not skip a file for which a lzip compressed version already exists. +Don't 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 existing lzip file and deletes the input file if both contents are identical. |