SYNOPSIS
bzip2 [ -cdfkqstvzVL123456789 ] [ filenames ... ]
bunzip2 [ -fkvsVL ] [ filenames ... ]
bzcat [ -s ] [ filenames ... ]
bzip2recover filename
OPTIONS
-c --stdout
Compress or decompress to standard output.
-d --decompress
Force decompression. bzip2, bunzip2 and bzcat are really the
same program, and the decision about what actions to take is
done on the basis of which name is used. This flag overrides
that mechanism, and forces bzip2 to decompress.
-z --compress
The complement to -d: forces compression, regardless of the
invocation name.
-t --test
Check integrity of the specified file(s), but don't decompress
them. This really performs a trial decompression and throws
away the result.
-f --force
Force overwrite of output files. Normally, bzip2 will not over-
write existing output files. Also forces bzip2 to break hard
links to files, which it otherwise wouldn't do.
bzip2 normally declines to decompress files which don't have the
correct magic header bytes. If forced (-f), however, it will
pass such files through unmodified. This is how GNU gzip
behaves.
-k --keep
Keep (don't delete) input files during compression or decompres-
sion.
-s --small
Reduce memory usage, for compression, decompression and testing.
Files are decompressed and tested using a modified algorithm
which only requires 2.5 bytes per block byte. This means any
file can be decompressed in 2300k of memory, albeit at about
half the normal speed.
During compression, -s selects a block size of 200k, which lim-
its memory use to around the same figure, at the expense of your
compression ratio. In short, if your machine is low on memory
(8 megabytes or less), use -s for everything. See MEMORY MAN-
AGEMENT below.
-q --quiet
Suppress non-essential warning messages. Messages pertaining to
I/O errors and other critical events will not be suppressed.
-v --verbose
Verbose mode -- show the compression ratio for each file pro-
cessed. Further -v's increase the verbosity level, spewing out
lots of information which is primarily of interest for diagnos-
tic purposes.
-L --license -V --version
Display the software version, license terms and conditions.
-1 (or --fast) to -9 (or --best)
Set the block size to 100 k, 200 k .. 900 k when compressing.
Has no effect when decompressing. See MEMORY MANAGEMENT below.
The --fast and --best aliases are primarily for GNU gzip compat-
ibility. In particular, --fast doesn't make things signifi-
cantly faster. And --best merely selects the default behaviour.
-- Treats all subsequent arguments as file names, even if they
start with a dash. This is so you can handle files with names
beginning with a dash, for example: bzip2 -- -myfilename.
--repetitive-fast --repetitive-best
These flags are redundant in versions 0.9.5 and above. They
provided some coarse control over the behaviour of the sorting
algorithm in earlier versions, which was sometimes useful.
0.9.5 and above have an improved algorithm which renders these
flags irrelevant
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