From 795b859eee96c700e8f3c3fe68e6a9a39d95797c Mon Sep 17 00:00:00 2001 From: Julian Seward Date: Sat, 24 Jun 2000 22:13:13 +0200 Subject: bzip2-1.0.1 --- bzip2.1.preformatted | 113 +++++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 100 insertions(+), 13 deletions(-) (limited to 'bzip2.1.preformatted') diff --git a/bzip2.1.preformatted b/bzip2.1.preformatted index 96b44be..9f18339 100644 --- a/bzip2.1.preformatted +++ b/bzip2.1.preformatted @@ -1,7 +1,11 @@ + +bzip2(1) bzip2(1) + + NNAAMMEE - bzip2, bunzip2 - a block-sorting file compressor, v0.9.5 + bzip2, bunzip2 - a block-sorting file compressor, v1.0 bzcat - decompresses files to stdout bzip2recover - recovers data from damaged bzip2 files @@ -54,6 +58,18 @@ DDEESSCCRRIIPPTTIIOONN filename.bz2 becomes filename filename.bz becomes filename filename.tbz2 becomes filename.tar + + + + 1 + + + + + +bzip2(1) bzip2(1) + + filename.tbz becomes filename.tar anyothername becomes anyothername.out @@ -109,6 +125,17 @@ DDEESSCCRRIIPPTTIIOONN you recover the original uncompressed data. You can use _b_z_i_p_2_r_e_c_o_v_e_r to try to recover data from damaged files. + + + 2 + + + + + +bzip2(1) bzip2(1) + + Return values: 0 for a normal exit, 1 for environmental problems (file not found, invalid flags, I/O errors, &c), 2 to indicate a corrupt compressed file, 3 for an internal @@ -163,6 +190,18 @@ OOPPTTIIOONNSS --qq ----qquuiieett Suppress non-essential warning messages. Messages pertaining to I/O errors and other critical events + + + + 3 + + + + + +bzip2(1) bzip2(1) + + will not be suppressed. --vv ----vveerrbboossee @@ -217,6 +256,18 @@ MMEEMMOORRYY MMAANNAAGGEEMMEENNTT Larger block sizes give rapidly diminishing marginal returns. Most of the compression comes from the first two + + + + 4 + + + + + +bzip2(1) bzip2(1) + + or three hundred k of block size, a fact worth bearing in mind when using _b_z_i_p_2 on small machines. It is also important to appreciate that the decompression memory @@ -270,6 +321,19 @@ MMEEMMOORRYY MMAANNAAGGEEMMEENNTT -9 7600k 3700k 2350k 828642 + + + + + 5 + + + + + +bzip2(1) bzip2(1) + + RREECCOOVVEERRIINNGG DDAATTAA FFRROOMM DDAAMMAAGGEEDD FFIILLEESS _b_z_i_p_2 compresses files in blocks, usually 900kbytes long. Each block is handled independently. If a media or trans- @@ -324,6 +388,18 @@ PPEERRFFOORRMMAANNCCEE NNOOTTEESS operate in, and then charges all over it in a fairly ran- dom fashion. This means that performance, both for com- pressing and decompressing, is largely determined by the + + + + 6 + + + + + +bzip2(1) bzip2(1) + + speed at which your machine can service cache misses. Because of this, small changes to the code to reduce the miss rate have been observed to give disproportionately @@ -337,14 +413,14 @@ CCAAVVEEAATTSS but the details of what the problem is sometimes seem rather misleading. - This manual page pertains to version 0.9.5 of _b_z_i_p_2_. Com- + This manual page pertains to version 1.0 of _b_z_i_p_2_. Com- pressed data created by this version is entirely forwards and backwards compatible with the previous public - releases, versions 0.1pl2 and 0.9.0, but with the follow- - ing exception: 0.9.0 and above can correctly decompress - multiple concatenated compressed files. 0.1pl2 cannot do - this; it will stop after decompressing just the first file - in the stream. + releases, versions 0.1pl2, 0.9.0 and 0.9.5, but with the + following exception: 0.9.0 and above can correctly decom- + press multiple concatenated compressed files. 0.1pl2 can- + not do this; it will stop after decompressing just the + first file in the stream. _b_z_i_p_2_r_e_c_o_v_e_r uses 32-bit integers to represent bit posi- tions in compressed files, so it cannot handle compressed @@ -355,21 +431,32 @@ CCAAVVEEAATTSS AAUUTTHHOORR Julian Seward, jseward@acm.org. + http://sourceware.cygnus.com/bzip2 http://www.muraroa.demon.co.uk The ideas embodied in _b_z_i_p_2 are due to (at least) the fol- - lowing people: Michael Burrows and David Wheeler (for the - block sorting transformation), David Wheeler (again, for + lowing people: Michael Burrows and David Wheeler (for the + block sorting transformation), David Wheeler (again, for the Huffman coder), Peter Fenwick (for the structured cod- ing model in the original _b_z_i_p_, and many refinements), and - Alistair Moffat, Radford Neal and Ian Witten (for the + Alistair Moffat, Radford Neal and Ian Witten (for the arithmetic coder in the original _b_z_i_p_)_. I am much indebted for their help, support and advice. See the man- - ual in the source distribution for pointers to sources of + ual in the source distribution for pointers to sources of documentation. Christian von Roques encouraged me to look - for faster sorting algorithms, so as to speed up compres- + for faster sorting algorithms, so as to speed up compres- sion. Bela Lubkin encouraged me to improve the worst-case compression performance. Many people sent patches, helped - with portability problems, lent machines, gave advice and + with portability problems, lent machines, gave advice and were generally helpful. + + + + + + + + 7 + + -- cgit v1.2.3-55-g6feb