diff options
author | Julian Seward <jseward@acm.org> | 2001-12-30 22:13:13 +0100 |
---|---|---|
committer | Julian Seward <jseward@acm.org> | 2001-12-30 22:13:13 +0100 |
commit | 099d844292f60f9d58914da29e5773204dc55e7a (patch) | |
tree | 04bdb38dbcd894d6fdbbc3253e216d029cade5c6 /bzip2.1 | |
parent | 795b859eee96c700e8f3c3fe68e6a9a39d95797c (diff) | |
download | bzip2-099d844292f60f9d58914da29e5773204dc55e7a.tar.gz bzip2-099d844292f60f9d58914da29e5773204dc55e7a.tar.bz2 bzip2-099d844292f60f9d58914da29e5773204dc55e7a.zip |
bzip2-1.0.2bzip2-1.0.2
Diffstat (limited to 'bzip2.1')
-rw-r--r-- | bzip2.1 | 56 |
1 files changed, 35 insertions, 21 deletions
@@ -1,7 +1,7 @@ | |||
1 | .PU | 1 | .PU |
2 | .TH bzip2 1 | 2 | .TH bzip2 1 |
3 | .SH NAME | 3 | .SH NAME |
4 | bzip2, bunzip2 \- a block-sorting file compressor, v1.0 | 4 | bzip2, bunzip2 \- a block-sorting file compressor, v1.0.2 |
5 | .br | 5 | .br |
6 | bzcat \- decompresses files to stdout | 6 | bzcat \- decompresses files to stdout |
7 | .br | 7 | .br |
@@ -197,7 +197,7 @@ to decompress. | |||
197 | .TP | 197 | .TP |
198 | .B \-z --compress | 198 | .B \-z --compress |
199 | The complement to \-d: forces compression, regardless of the | 199 | The complement to \-d: forces compression, regardless of the |
200 | invokation name. | 200 | invocation name. |
201 | .TP | 201 | .TP |
202 | .B \-t --test | 202 | .B \-t --test |
203 | Check integrity of the specified file(s), but don't decompress them. | 203 | Check integrity of the specified file(s), but don't decompress them. |
@@ -211,6 +211,10 @@ existing output files. Also forces | |||
211 | .I bzip2 | 211 | .I bzip2 |
212 | to break hard links | 212 | to break hard links |
213 | to files, which it otherwise wouldn't do. | 213 | to files, which it otherwise wouldn't do. |
214 | |||
215 | bzip2 normally declines to decompress files which don't have the | ||
216 | correct magic header bytes. If forced (-f), however, it will pass | ||
217 | such files through unmodified. This is how GNU gzip behaves. | ||
214 | .TP | 218 | .TP |
215 | .B \-k --keep | 219 | .B \-k --keep |
216 | Keep (don't delete) input files during compression | 220 | Keep (don't delete) input files during compression |
@@ -239,9 +243,13 @@ information which is primarily of interest for diagnostic purposes. | |||
239 | .B \-L --license -V --version | 243 | .B \-L --license -V --version |
240 | Display the software version, license terms and conditions. | 244 | Display the software version, license terms and conditions. |
241 | .TP | 245 | .TP |
242 | .B \-1 to \-9 | 246 | .B \-1 (or \-\-fast) to \-9 (or \-\-best) |
243 | Set the block size to 100 k, 200 k .. 900 k when compressing. Has no | 247 | Set the block size to 100 k, 200 k .. 900 k when compressing. Has no |
244 | effect when decompressing. See MEMORY MANAGEMENT below. | 248 | effect when decompressing. See MEMORY MANAGEMENT below. |
249 | The \-\-fast and \-\-best aliases are primarily for GNU gzip | ||
250 | compatibility. In particular, \-\-fast doesn't make things | ||
251 | significantly faster. | ||
252 | And \-\-best merely selects the default behaviour. | ||
245 | .TP | 253 | .TP |
246 | .B \-- | 254 | .B \-- |
247 | Treats all subsequent arguments as file names, even if they start | 255 | Treats all subsequent arguments as file names, even if they start |
@@ -352,11 +360,11 @@ undamaged. | |||
352 | 360 | ||
353 | .I bzip2recover | 361 | .I bzip2recover |
354 | takes a single argument, the name of the damaged file, | 362 | takes a single argument, the name of the damaged file, |
355 | and writes a number of files "rec0001file.bz2", | 363 | and writes a number of files "rec00001file.bz2", |
356 | "rec0002file.bz2", etc, containing the extracted blocks. | 364 | "rec00002file.bz2", etc, containing the extracted blocks. |
357 | The output filenames are designed so that the use of | 365 | The output filenames are designed so that the use of |
358 | wildcards in subsequent processing -- for example, | 366 | wildcards in subsequent processing -- for example, |
359 | "bzip2 -dc rec*file.bz2 > recovered_data" -- lists the files in | 367 | "bzip2 -dc rec*file.bz2 > recovered_data" -- processes the files in |
360 | the correct order. | 368 | the correct order. |
361 | 369 | ||
362 | .I bzip2recover | 370 | .I bzip2recover |
@@ -397,27 +405,31 @@ I/O error messages are not as helpful as they could be. | |||
397 | tries hard to detect I/O errors and exit cleanly, but the details of | 405 | tries hard to detect I/O errors and exit cleanly, but the details of |
398 | what the problem is sometimes seem rather misleading. | 406 | what the problem is sometimes seem rather misleading. |
399 | 407 | ||
400 | This manual page pertains to version 1.0 of | 408 | This manual page pertains to version 1.0.2 of |
401 | .I bzip2. | 409 | .I bzip2. |
402 | Compressed | 410 | Compressed data created by this version is entirely forwards and |
403 | data created by this version is entirely forwards and backwards | 411 | backwards compatible with the previous public releases, versions |
404 | compatible with the previous public releases, versions 0.1pl2, 0.9.0 | 412 | 0.1pl2, 0.9.0, 0.9.5, 1.0.0 and 1.0.1, but with the following |
405 | and 0.9.5, | 413 | exception: 0.9.0 and above can correctly decompress multiple |
406 | but with the following exception: 0.9.0 and above can correctly | 414 | concatenated compressed files. 0.1pl2 cannot do this; it will stop |
407 | decompress multiple concatenated compressed files. 0.1pl2 cannot do | 415 | after decompressing just the first file in the stream. |
408 | this; it will stop after decompressing just the first file in the | ||
409 | stream. | ||
410 | 416 | ||
411 | .I bzip2recover | 417 | .I bzip2recover |
412 | uses 32-bit integers to represent bit positions in | 418 | versions prior to this one, 1.0.2, used 32-bit integers to represent |
413 | compressed files, so it cannot handle compressed files more than 512 | 419 | bit positions in compressed files, so it could not handle compressed |
414 | megabytes long. This could easily be fixed. | 420 | files more than 512 megabytes long. Version 1.0.2 and above uses |
421 | 64-bit ints on some platforms which support them (GNU supported | ||
422 | targets, and Windows). To establish whether or not bzip2recover was | ||
423 | built with such a limitation, run it without arguments. In any event | ||
424 | you can build yourself an unlimited version if you can recompile it | ||
425 | with MaybeUInt64 set to be an unsigned 64-bit integer. | ||
426 | |||
427 | |||
415 | 428 | ||
416 | .SH AUTHOR | 429 | .SH AUTHOR |
417 | Julian Seward, jseward@acm.org. | 430 | Julian Seward, jseward@acm.org. |
418 | 431 | ||
419 | http://sourceware.cygnus.com/bzip2 | 432 | http://sources.redhat.com/bzip2 |
420 | http://www.muraroa.demon.co.uk | ||
421 | 433 | ||
422 | The ideas embodied in | 434 | The ideas embodied in |
423 | .I bzip2 | 435 | .I bzip2 |
@@ -434,6 +446,8 @@ indebted for their help, support and advice. See the manual in the | |||
434 | source distribution for pointers to sources of documentation. Christian | 446 | source distribution for pointers to sources of documentation. Christian |
435 | von Roques encouraged me to look for faster sorting algorithms, so as to | 447 | von Roques encouraged me to look for faster sorting algorithms, so as to |
436 | speed up compression. Bela Lubkin encouraged me to improve the | 448 | speed up compression. Bela Lubkin encouraged me to improve the |
437 | worst-case compression performance. Many people sent patches, helped | 449 | worst-case compression performance. |
450 | The bz* scripts are derived from those of GNU gzip. | ||
451 | Many people sent patches, helped | ||
438 | with portability problems, lent machines, gave advice and were generally | 452 | with portability problems, lent machines, gave advice and were generally |
439 | helpful. | 453 | helpful. |