pristine-bz2(1) [debian man page]
PRISTINE-BZ2(1) pristine-bz2 PRISTINE-BZ2(1) NAME
pristine-bz2 - regenerate pristine bz2 files SYNOPSIS
pristine-bz2 [-vdk] gendelta file.bz2 delta pristine-bz2 [-vdk] genbz2 delta file DESCRIPTION
This is a complement to the pristine-tar(1) command. Normally you don't need to run it by hand, since pristine-tar calls it as necessary to handle .tar.bz2 files. pristine-bz2 gendelta takes the specified bz2 file, and generates a small binary delta file that can later be used by pristine-bz2 genbz2 to recreate the original file. pristine-bz2 genbz2 takes the specified delta file, and compresses the specified input file (which must be identical to the contents of the original bz2 file). The resulting file will be identical to the original gz file used to create the delta. The approach used to regenerate the original bz2 file is to figure out how it was produced -- what compression level was used, whether it was built with bzip2(1) or with pbzip2(1). Note that other tools exist, like bzip2smp or dbzip2, but they are said to be bit-identical with bzip2. Anyway, bzip2 looks like the most widespread implementation, so it's hard to find bzip2 files that make pristine-bz2 fail. Please report! The deprecated bzip1 compression method hasn't been implemented. If the delta filename is "-", pristine-bz2 reads or writes it to stdio. OPTIONS
-v Verbose mode, show each command that is run. -d Debug mode. -k Don't clean up the temporary directory on exit. -t Try harder to determine how to generate deltas of difficult bz2 files. ENVIRONMENT
TMPDIR Specifies a location to place temporary files, other than the default. AUTHOR
Joey Hess <joeyh@debian.org>, Faidon Liambotis <paravoid@debian.org>, Cyril Brulebois <cyril.brulebois@enst-bretagne.fr> Licensed under the GPL, version 2. perl v5.14.2 2013-06-01 PRISTINE-BZ2(1)
Check Out this Related Man Page
bz2(3trf) bz2(3trf) NAME
bz2 - Data compression "bz2" SYNOPSIS
package require Tcl ?8.2? package require Trf ?2.1.3? bz2 ?options...? ?data? DESCRIPTION
The command bz2 is one of several data compressions provided by the package trf. See trf-intro for an overview of the whole package. The command is based on the Burroughs-Wheeler transformation as implemented by the bzip2 compression library (http://sources.red- hat.com/bzip2/). bz2 ?options...? ?data? -mode compress|decompress This option has to be present and is always understood by the compression. For immediate mode the argument value specifies the operation to use. For an attached compress it specifies the operation to use for writing. Reading will automatically use the reverse operation. See section IMMEDIATE versus ATTACHED for explana- tions of these two terms. Beyond the argument values listed above all unique abbreviations are recognized too. Compress causes the compression of arbitrary (most likely binary) data. Decompression does the reverse . -level integer Specifies the compression level. Is either the string default or an integer number in the range 1 (minimal compression) to 9 (maximal compression). -attach channel The presence/absence of this option determines the main operation mode of the transformation. If present the transformation will be stacked onto the channel whose handle was given to the option and run in attached mode. More about this in section IMMEDIATE versus ATTACHED. If the option is absent the transformation is used in immediate mode and the options listed below are recognized. More about this in section IMMEDIATE versus ATTACHED. -in channel This options is legal if and only if the transformation is used in immediate mode. It provides the handle of the channel the data to transform has to be read from. If the transformation is in immediate mode and this option is absent the data to transform is expected as the last argument to the transformation. -out channel This options is legal if and only if the transformation is used in immediate mode. It provides the handle of the channel the generated transformation result is written to. If the transformation is in immediate mode and this option is absent the generated data is returned as the result of the com- mand itself. IMMEDIATE VERSUS ATTACHED
The transformation distinguishes between two main ways of using it. These are the immediate and attached operation modes. For the attached mode the option -attach is used to associate the transformation with an existing channel. During the execution of the com- mand no transformation is performed, instead the channel is changed in such a way, that from then on all data written to or read from it passes through the transformation and is modified by it according to the definition above. This attachment can be revoked by executing the command unstack for the chosen channel. This is the only way to do this at the Tcl level. In the second mode, which can be detected by the absence of option -attach, the transformation immediately takes data from either its com- mandline or a channel, transforms it, and returns the result either as result of the command, or writes it into a channel. The mode is named after the immediate nature of its execution. Where the data is taken from, and delivered to, is governed by the presence and absence of the options -in and -out. It should be noted that this ability to immediately read from and/or write to a channel is an historic artifact which was introduced at the beginning of Trf's life when Tcl version 7.6 was current as this and earlier versions have trouble to deal with characters embedded into either input or output. SEE ALSO
bz2, trf-intro, zip KEYWORDS
Burroughs-Wheeler, bz2, compression, data compression, decompression COPYRIGHT
Copyright (c) 1996-2003, Andreas Kupries <andreas_kupries@users.sourceforge.net> Trf transformer commands 2.1.3 bz2(3trf)