bzip2(1) General Commands Manual bzip2(1) (NAME) bzip2, bunzip2 - 1.0.8 bzcat - bzip2recover - bzip2 (SYNOPSIS) bzip2 [ -cdfkqstvzVL123456789 ] [ filenames ... ] bzip2 [ -h|--help ] bunzip2 [ -fkvsVL ] [ filenames ... ] bunzip2 [ -h|--help ] bzcat [ -s ] [ filenames ... ] bzcat [ -h|--help ] bzip2recover filename (DESCRIPTION) bzip2 - (Burrows-Wheeler) . LZ77/LZ78 PPM . GNU gzip . bzip2 . "original_name.bz2" . . ( MS-DOS) . bzip2 bunzip2 . -f . bzip2 . bzip2 . bunzip2 ( bzip2 -d) . bzip2 . bzip2 : filename.bz2 filename filename.bz filename filename.tbz2 filename.tar filename.tbz filename.tar anyothername anyothername.out .bz2 .bz .tbz2 .tbz bzip2 .out . . bunzip2 . . (-t) . -c . . stdout . . 0.9.0 bzip2 . bzip2 . bzcat ( bzip2 -dc) . bzip2 BZIP2 BZIP . . . . ( ) . bzip2 - (CRC) . bzip2 ( ) . . . . bzip2recover . : ( / ) ( ) (panic) bzip2 . (OPTIONS) -c --stdout . -d --decompress . bzip2 bunzip2 bzcat . bzip2 . -z --compress -d: . -t --test () . . -f --force . bzip2 . bzip2 (hard links) . bzip2 . (-f) . GNU gzip . -k --keep ( ) . -s --small . . . -s . ( ) -s . . -q --quiet . / . -v --verbose -- . -v . -h --help . -L --license -V --version . -1 (or --fast) to -9 (or --best) ... . . . --fast --best GNU gzip . --fast --best . -- . : bzip2 -- -myfilename. --repetitive-fast --repetitive-best 0.9.5 . . 0.9.5 . (MEMORY MANAGEMENT) bzip2 . . -1 -9 () . bunzip2 . -1 -9 . : Compression: 400 k + ( 8 x block size ) Decompression: 100 k + ( 4 x block size ), or 100 k + ( 2.5 x block size ) . bzip2 . . bunzip2 . bunzip2 . . -s . . . -- . . -9 400 k + 20000 * 8 = 560 . 100 k + 20000 * 4 = 180 . . (Calgary Text Compression Corpus) . . . Compress Decompress Decompress Corpus Flag usage usage -s usage Size -1 1200k 500k 350k 914704 -2 2000k 900k 600k 877703 -3 2800k 1300k 850k 860338 -4 3600k 1700k 1100k 846899 -5 4400k 2100k 1350k 845160 -6 5200k 2500k 1600k 838626 -7 6100k 2900k 1850k 834096 -8 6800k 3300k 2100k 828642 -9 7600k 3700k 2350k 828642 (RECOVERING DATA FROM DAMAGED FILES) bzip2 . . bz2. . - . CRC . bzip2recover bz2. bz2. . bzip2 -t . bzip2recover "rec00001file.bz2" "rec00002file.bz2" . (wildcards) -- "bzip2 -dc rec*file.bz2 > recovered_data" -- . bzip2recover bz2. . . . (PERFORMANCE NOTES) . "aabaabaabaab ..." ( ) . 0.9.5 . . . -vvvv . . bzip2 . (cache misses) . . bzip2 () . (CAVEATS) / . bzip2 / . 1.0.8 bzip2 . 0.1pl2 0.9.0 0.9.5 1.0.0 1.0.1 1.0.2 : 0.9.0 . 0.1pl2 . bzip2recover 1.0.2 - . 1.0.2 - ( GNU ) . bzip2recover . MaybeUInt64 - . (AUTHOR) Julian Seward, jseward@acm.org. https://sourceware.org/bzip2/ bzip2 () : Michael Burrows David Wheeler ( ) David Wheeler ( ) Peter Fenwick ( bzip ) Alistair Moffat Radford Neal Ian Witten ( bzip ). . . Christian von Roques . Bela Lubkin . Donna Robinson XML . *bz GNU gzip . (patches) . (REPORTING BUGS) : . (COPYRIGHT) (C) 1996-2019 Julian R Seward. . bzip2 . (SEE ALSO) gzip(1), zip(1), tar(1), lzma(1), xz(1) bzip2(1)