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pbzip2(1)		    General Commands Manual		     pbzip2(1)

NAME
       pbzip2  -  parallel bzip2 file compressor, v1.1.10

SYNOPSIS
       pbzip2 [	-123456789 ] [ -b#cdfhklm#p#qrS#tvVz ] [ filenames ...	]

DESCRIPTION
       pbzip2  is  a  parallel	implementation of the bzip2 block-sorting file
       compressor that uses pthreads and achieves near-linear speedup  on  SMP
       machines.  The  output  of  this	version	is fully compatible with bzip2
       v1.0.2 or newer (ie: anything compressed	 with  pbzip2  can  be	decom-
       pressed with bzip2).

       pbzip2  should  work  on	 any system that has a pthreads	compatible C++
       compiler	(such as gcc). It has been tested on: Linux, Windows (cygwin),
       Solaris,	Tru64/OSF1, HP-UX, and Irix.

       The  default settings for pbzip2	will work well in most cases. The only
       switch you will likely need to use is -d	to decompress files and	-p  to
       set  the	 #  of	processors for pbzip2 to use if	autodetect is not sup-
       ported on your system, or you want to use a specific # of CPUs.

OPTIONS
       -b#    Where # is block size in 100k steps (default 9 = 900k)

       -c, --stdout
	      Output to	standard out (stdout)

       -d,--decompress
	      Decompress file

       -f,--force
	      Force, overwrite existing	output file

       -h,--help
	      Print this help message

       -k,--keep
	      Keep input file, do not delete

       -l,--loadavg
	      Load average determines max number processors to use

       -m#    Where # is max memory usage in 1MB steps (default	100 = 100MB)

       -p#    Where # is the number of processors (default: autodetect)

       -q,--quiet
	      Quiet mode (default)

       -r,--read
	      Read entire input	file into RAM and split	between	processors

       -S#    Child thread stack size in 1KB steps (default stack size if  un-
	      specified)

       -t,--test
	      Test compressed file integrity

       -v,--verbose
	      Verbose mode

       -V     Display version info for pbzip2 then exit

       -z,--compress
	      Compress file (default)

       -1,--fast ... -9,--best
	      Set BWT block size to 100k .. 900k (default 900k).

       --ignore-trailing-garbage=#
	      Ignore trailing garbage flag (1 -	ignored; 0 - forbidden)

       If  no  file  names  are	 given,	pbzip2 compresses or decompresses from
       standard	input to standard output.

FILE SIZES
       You should be able to compress files larger than	4GB with pbzip2.

       Files that are compressed with pbzip2 are broken	 up  into  pieces  and
       each individual piece is	compressed.  This is how pbzip2	runs faster on
       multiple	CPUs since the pieces can be compressed	 simultaneously.   The
       final  .bz2  file may be	slightly larger	than if	it was compressed with
       the regular bzip2 program due to	this file splitting (usually less than
       0.2%  larger).	Files  that  are compressed with pbzip2	will also gain
       considerable speedup when decompressed using pbzip2.

       Files that were compressed using	bzip2 will not see speedup since bzip2
       packages	the data into a	single chunk that cannot be split between pro-
       cessors.

EXAMPLES
       Example 1: pbzip2 myfile.tar

       This example will compress the file "myfile.tar"	 into  the  compressed
       file "myfile.tar.bz2". It will use the autodetected # of	processors (or
       2 processors if autodetect not supported) with the default  file	 block
       size of 900k and	default	BWT block size of 900k.

       Example 2: pbzip2 -b15k myfile.tar

       This  example  will  compress the file "myfile.tar" into	the compressed
       file "myfile.tar.bz2". It will use the autodetected # of	processors (or
       2  processors  if  autodetect  not supported) with a file block size of
       1500k and a BWT block size of 900k. The file "myfile.tar" will  not  be
       deleted after compression is finished.

       Example 3: pbzip2 -p4 -r	-5 myfile.tar second*.txt

       This  example  will  compress the file "myfile.tar" into	the compressed
       file "myfile.tar.bz2". It will use 4 processors with a BWT  block  size
       of  500k.  The file block size will be the size of "myfile.tar" divided
       by 4 (# of processors) so that the data will be split evenly among each
       processor.   This  requires  you	have enough RAM	for pbzip2 to read the
       entire file into	memory for compression.	Pbzip2 will then use the  same
       options	to  compress  all  other  files	 that match the	wildcard "sec-
       ond*.txt" in that directory.

       Example 4: tar cf myfile.tar.bz2	--use-compress-prog=pbzip2 dir_to_com-
       press/
       Example 4: tar -c directory_to_compress/	| pbzip2 -c > myfile.tar.bz2

       These  examples	will  compress the data	being given to pbzip2 via pipe
       from TAR	into the compressed file "myfile.tar.bz2".  It	will  use  the
       autodetected  #	of  processors (or 2 processors	if autodetect not sup-
       ported) with the	default	file block size	of 900k	and default BWT	 block
       size  of	 900k.	 TAR  is  collecting all of the	files from the "direc-
       tory_to_compress/" directory and	passing	 the  data  to	pbzip2	as  it
       works.

       Example 5: pbzip2 -d -m500 myfile.tar.bz2

       This  example will decompress the file "myfile.tar.bz2" into the	decom-
       pressed file "myfile.tar". It will use the autodetected # of processors
       (or 2 processors	if autodetect not supported). It will use a maximum of
       500MB of	memory for decompression.  The switches	-b, -r,	and -1..-9 are
       not valid for decompression.

       Example 6: pbzip2 -dc myfile.tar.bz2 | tar x

       This example will decompress and	untar the file "myfile.tar.bz2"	piping
       the output of the decompressing pbzip2 to tar.

       Example 7: pbzip2 -c < myfile.txt > myfile.txt.bz2

       This example will read myfile.txt from standard input compressing it to
       standard	output which is	redirected to to myfile.txt.bz2.

SEE ALSO
       bzip2(1)	gzip(1)	lzip(1)	rzip(1)	zip(1)

AUTHOR
       Jeff Gilchrist

       http://compression.ca

								     pbzip2(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | FILE SIZES | EXAMPLES | SEE ALSO | AUTHOR

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