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Diffstat (limited to 'doc/clzip.texinfo')
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diff --git a/doc/clzip.texinfo b/doc/clzip.texinfo index 85396ab..284ed3f 100644 --- a/doc/clzip.texinfo +++ b/doc/clzip.texinfo @@ -1,12 +1,13 @@ \input texinfo @c -*-texinfo-*- @c %**start of header @setfilename clzip.info +@documentencoding ISO-8859-15 @settitle Clzip Manual @finalout @c %**end of header -@set UPDATED 18 May 2011 -@set VERSION 1.2 +@set UPDATED 25 February 2012 +@set VERSION 1.3 @dircategory Data Compression @direntry @@ -44,7 +45,7 @@ This manual is for Clzip (version @value{VERSION}, @value{UPDATED}). @end menu @sp 1 -Copyright @copyright{} 2010, 2011 Antonio Diaz Diaz. +Copyright @copyright{} 2010, 2011, 2012 Antonio Diaz Diaz. This manual is free documentation: you have unlimited permission to copy, distribute and modify it. @@ -65,6 +66,9 @@ compatible with lzip-1.4 or newer. Clzip is in fact a C language version of lzip, intended for embedded devices or systems lacking a C++ compiler. +If you ever need to recover data from a damaged lzip file, try the +lziprecover program. + Clzip replaces every file given in the command line with a compressed version of itself, with the name "original_name.lz". Each compressed file has the same modification date, permissions, and, when possible, @@ -82,11 +86,11 @@ or more compressed files. The result is the concatenation of the corresponding uncompressed files. Integrity testing of concatenated compressed files is also supported. -Clzip can produce multimember files and safely recover, with lziprecover, -the undamaged members in case of file damage. Clzip can also split the -compressed output in volumes of a given size, even when reading from -standard input. This allows the direct creation of multivolume -compressed tar archives. +Clzip can produce multi-member files and safely recover, with +lziprecover, the undamaged members in case of file damage. Clzip can +also split the compressed output in volumes of a given size, even when +reading from standard input. This allows the direct creation of +multivolume compressed tar archives. The amount of memory required for compression is about 5 MiB plus 1 or 2 times the dictionary size limit (1 if input file size is less than @@ -210,10 +214,10 @@ Print an informative help message describing the options and exit. @itemx --version Print the version number of clzip on the standard output and exit. -@item -b @var{size} -@itemx --member-size=@var{size} -Produce a multimember file and set the member size limit to @var{size} -bytes. Minimum member size limit is 100kB. Small member size may degrade +@item -b @var{bytes} +@itemx --member-size=@var{bytes} +Produce a multi-member file and set the member size limit to @var{bytes}. +Minimum member size limit is 100kB. Small member size may degrade compression ratio, so use it only when needed. The default is to produce single-member files. @@ -229,7 +233,7 @@ Decompress. @item -f @itemx --force -Force overwrite of output file. +Force overwrite of output files. @item -F @itemx --recompress @@ -240,8 +244,8 @@ Force recompression of files whose name already has the @samp{.lz} or @itemx --keep Keep (don't delete) input files during compression or decompression. -@item -m @var{length} -@itemx --match-length=@var{length} +@item -m @var{bytes} +@itemx --match-length=@var{bytes} Set the match length limit in bytes. After a match this long is found, the search is finished. Valid values range from 5 to 273. Larger values usually give better compression ratios but longer compression times. @@ -259,25 +263,25 @@ compressing and splitting the output in volumes. @itemx --quiet Quiet operation. Suppress all messages. -@item -s @var{size} -@itemx --dictionary-size=@var{size} +@item -s @var{bytes} +@itemx --dictionary-size=@var{bytes} Set the dictionary size limit in bytes. Valid values range from 4KiB to 512MiB. Clzip will use the smallest possible dictionary size for each member without exceeding this limit. Note that dictionary sizes are quantized. If the specified size does not match one of the valid sizes, -it will be rounded upwards by adding up to (@var{size} / 16) to it. +it will be rounded upwards by adding up to (@var{bytes} / 16) to it. For maximum compression you should use a dictionary size limit as large as possible, but keep in mind that the decompression memory requirement is affected at compression time by the choice of dictionary size limit. -@item -S @var{size} -@itemx --volume-size=@var{size} +@item -S @var{bytes} +@itemx --volume-size=@var{bytes} Split the compressed output into several volume files with names @samp{original_name00001.lz}, @samp{original_name00002.lz}, etc, and set -the volume size limit to @var{size} bytes. Each volume is a complete, -maybe multimember, lzip file. Minimum volume size limit is 100kB. Small -volume size may degrade compression ratio, so use it only when needed. +the volume size limit to @var{bytes}. Each volume is a complete, maybe +multi-member, lzip file. Minimum volume size limit is 100kB. Small volume +size may degrade compression ratio, so use it only when needed. @item -t @itemx --test @@ -287,8 +291,8 @@ Use it together with @samp{-v} to see information about the file. @item -v @itemx --verbose -Verbose mode. -When compressing, show the compression ratio for each file processed. +Verbose mode.@* +When compressing, show the compression ratio for each file processed.@* When decompressing or testing, further -v's (up to 4) increase the verbosity level, showing status, dictionary size, compression ratio, and trailer contents (CRC, data size, member size). @@ -404,7 +408,7 @@ Size of the uncompressed original data. @item Member size (8 bytes) Total size of the member, including header and trailer. This facilitates -safe recovery of undamaged members from multimember files. +safe recovery of undamaged members from multi-member files. @end table @@ -415,15 +419,15 @@ safe recovery of undamaged members from multimember files. WARNING! Even if clzip is bug-free, other causes may result in a corrupt compressed file (bugs in the system libraries, memory errors, etc). -Therefore, if the data you are going to compress is important give the +Therefore, if the data you are going to compress is important, give the @samp{--keep} option to clzip and do not remove the original file until -you verify the compressed file with a command like @w{@samp{clzip -cd -file.lz | cmp file -}}. +you verify the compressed file with a command like +@w{@samp{clzip -cd file.lz | cmp file -}}. @sp 1 @noindent -Example 1: Replace a regular file with its compressed version file.lz -and show the compression ratio. +Example 1: Replace a regular file with its compressed version +@samp{file.lz} and show the compression ratio. @example clzip -v file @@ -431,8 +435,8 @@ clzip -v file @sp 1 @noindent -Example 2: Like example 1 but the created file.lz is multimember with a -member size of 1MiB. The compression ratio is not shown. +Example 2: Like example 1 but the created @samp{file.lz} is multi-member +with a member size of 1MiB. The compression ratio is not shown. @example clzip -b 1MiB file @@ -440,8 +444,9 @@ clzip -b 1MiB file @sp 1 @noindent -Example 3: Restore a regular file from its compressed version file.lz. -If the operation is successful, file.lz is removed. +Example 3: Restore a regular file from its compressed version +@samp{file.lz}. If the operation is successful, @samp{file.lz} is +removed. @example clzip -d file.lz @@ -449,8 +454,8 @@ clzip -d file.lz @sp 1 @noindent -Example 4: Verify the integrity of the compressed file file.lz and show -status. +Example 4: Verify the integrity of the compressed file @samp{file.lz} +and show status. @example clzip -tv file.lz @@ -459,7 +464,7 @@ clzip -tv file.lz @sp 1 @noindent Example 5: Compress a whole floppy in /dev/fd0 and send the output to -file.lz. +@samp{file.lz}. @example clzip -c /dev/fd0 > file.lz @@ -467,8 +472,8 @@ clzip -c /dev/fd0 > file.lz @sp 1 @noindent -Example 6: Decompress file.lz partially until 10KiB of decompressed data -are produced. +Example 6: Decompress @samp{file.lz} partially until 10KiB of +decompressed data are produced. @example clzip -cd file.lz | dd bs=1024 count=10 @@ -476,7 +481,16 @@ clzip -cd file.lz | dd bs=1024 count=10 @sp 1 @noindent -Example 7: Create a multivolume compressed tar archive with a volume +Example 7: Decompress @samp{file.lz} partially from decompressed byte +10000 to decompressed byte 15000 (5000 bytes are produced). + +@example +clzip -cd file.lz | dd bs=1000 skip=10 count=5 +@end example + +@sp 1 +@noindent +Example 8: Create a multivolume compressed tar archive with a volume size of 1440KiB. @example @@ -485,7 +499,7 @@ tar -c some_directory | clzip -S 1440KiB -o volume_name @sp 1 @noindent -Example 8: Extract a multivolume compressed tar archive. +Example 9: Extract a multivolume compressed tar archive. @example clzip -cd volume_name*.lz | tar -xf - @@ -493,12 +507,12 @@ clzip -cd volume_name*.lz | tar -xf - @sp 1 @noindent -Example 9: Create a multivolume compressed backup of a big database file -with a volume size of 650MB, where each volume is a multimember file -with a member size of 32MiB. +Example 10: Create a multivolume compressed backup of a big database +file with a volume size of 650MB, where each volume is a multi-member +file with a member size of 32MiB. @example -clzip -b 32MiB -S 650MB big_database +clzip -b 32MiB -S 650MB big_db @end example |