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diff --git a/doc/clzip.info b/doc/clzip.info index 41723f3..263affa 100644 --- a/doc/clzip.info +++ b/doc/clzip.info @@ -3,7 +3,7 @@ clzip.texinfo. INFO-DIR-SECTION Data Compression START-INFO-DIR-ENTRY -* Clzip: (clzip). Data compressor based on the LZMA algorithm +* Clzip: (clzip). LZMA lossless data compressor END-INFO-DIR-ENTRY @@ -12,17 +12,17 @@ File: clzip.info, Node: Top, Next: Introduction, Up: (dir) Clzip Manual ************ -This manual is for Clzip (version 1.5-pre1, 13 May 2013). +This manual is for Clzip (version 1.5-pre2, 17 July 2013). * Menu: -* Introduction:: Purpose and features of clzip -* Algorithm:: How clzip compresses the data -* Invoking Clzip:: Command line interface -* File Format:: Detailed format of the compressed file -* Examples:: A small tutorial with examples -* Problems:: Reporting bugs -* Concept Index:: Index of concepts +* Introduction:: Purpose and features of clzip +* Algorithm:: How clzip compresses the data +* Invoking clzip:: Command line interface +* File format:: Detailed format of the compressed file +* Examples:: A small tutorial with examples +* Problems:: Reporting bugs +* Concept index:: Index of concepts Copyright (C) 2010, 2011, 2012, 2013 Antonio Diaz Diaz. @@ -36,23 +36,39 @@ File: clzip.info, Node: Introduction, Next: Algorithm, Prev: Top, Up: Top 1 Introduction ************** -Clzip is a lossless data compressor based on the LZMA algorithm, with -very safe integrity checking and a user interface similar to the one of -gzip or bzip2. Clzip decompresses almost as fast as gzip and compresses -better than bzip2, which makes it well suited for software distribution -and data archiving. +Clzip is a lossless data compressor with a user interface similar to the +one of gzip or bzip2. Clzip decompresses almost as fast as gzip and +compresses more than bzip2, which makes it well suited for software +distribution and data archiving. Clzip is a clean implementation of the +LZMA algorithm. - Clzip uses the same well-defined exit status values used by bzip2, -which makes it safer when used in pipes or scripts than compressors -returning ambiguous warning values, like gzip. + Clzip uses the same well-defined exit status values used by lzip and +bzip2, which makes it safer when used in pipes or scripts than +compressors returning ambiguous warning values, like gzip. Clzip uses the lzip file format; the files produced by clzip are -fully compatible with lzip-1.4 or newer. Clzip is in fact a C language -version of lzip, intended for embedded devices or systems lacking a C++ -compiler. +fully compatible with lzip-1.4 or newer, and can be rescued with +lziprecover. Clzip is in fact a C language version of lzip, intended +for embedded devices or systems lacking a C++ compiler. + + The lzip file format is designed for long-term data archiving and +provides very safe integrity checking. The member trailer stores the +32-bit CRC of the original data, the size of the original data and the +size of the member. These values, together with the value remaining in +the range decoder and the end-of-stream marker, provide a 4 factor +integrity checking which guarantees that the decompressed version of the +data is identical to the original. This guards against corruption of the +compressed data, and against undetected bugs in clzip (hopefully very +unlikely). The chances of data corruption going undetected are +microscopic. Be aware, though, that the check occurs upon decompression, +so it can only tell you that something is wrong. It can't help you +recover the original uncompressed data. If you ever need to recover data from a damaged lzip file, try the -lziprecover program. +lziprecover program. Lziprecover makes lzip files resistant to bit-flip +(one of the most common forms of data corruption), and provides data +recovery capabilities, including error-checked merging of damaged copies +of a file. Clzip replaces every file given in the command line with a compressed version of itself, with the name "original_name.lz". Each compressed @@ -99,20 +115,8 @@ filename.lz becomes filename filename.tlz becomes filename.tar anyothername becomes anyothername.out - As a self-check for your protection, clzip stores in the member -trailer the 32-bit CRC of the original data, the size of the original -data and the size of the member. These values, together with the value -remaining in the range decoder and the end-of-stream marker, provide a -very safe 4 factor integrity checking which guarantees that the -decompressed version of the data is identical to the original. This -guards against corruption of the compressed data, and against -undetected bugs in clzip (hopefully very unlikely). The chances of data -corruption going undetected are microscopic. Be aware, though, that the -check occurs upon decompression, so it can only tell you that something -is wrong. It can't help you recover the original uncompressed data. - -File: clzip.info, Node: Algorithm, Next: Invoking Clzip, Prev: Introduction, Up: Top +File: clzip.info, Node: Algorithm, Next: Invoking clzip, Prev: Introduction, Up: Top 2 Algorithm *********** @@ -173,9 +177,9 @@ range encoding), Igor Pavlov (for putting all the above together in LZMA), and Julian Seward (for bzip2's CLI and the idea of unzcrash). -File: clzip.info, Node: Invoking Clzip, Next: File Format, Prev: Algorithm, Up: Top +File: clzip.info, Node: Invoking clzip, Next: File format, Prev: Algorithm, Up: Top -3 Invoking Clzip +3 Invoking clzip **************** The format for running clzip is: @@ -278,10 +282,10 @@ The format for running clzip is: `--verbose' Verbose mode. When compressing, show the compression ratio for each file - processed. + processed. A second -v shows the progress of compression. When decompressing or testing, further -v's (up to 4) increase the - verbosity level, showing status, dictionary size, compression - ratio, and trailer contents (CRC, data size, member size). + verbosity level, showing status, compression ratio, dictionary + size, and trailer contents (CRC, data size, member size). `-1 .. -9' Set the compression parameters (dictionary size and match length @@ -333,9 +337,9 @@ invalid input file, 3 for an internal consistency error (eg, bug) which caused clzip to panic. -File: clzip.info, Node: File Format, Next: Examples, Prev: Invoking Clzip, Up: Top +File: clzip.info, Node: File format, Next: Examples, Prev: Invoking clzip, Up: Top -4 File Format +4 File format ************* Perfection is reached, not when there is no longer anything to add, but @@ -389,7 +393,8 @@ additional information before, between, or after them. `Lzma stream' The lzma stream, finished by an end of stream marker. Uses default - values for encoder properties. + values for encoder properties. See the lzip manual for a full + description. `CRC32 (4 bytes)' CRC of the uncompressed original data. @@ -405,7 +410,7 @@ additional information before, between, or after them. -File: clzip.info, Node: Examples, Next: Problems, Prev: File Format, Up: Top +File: clzip.info, Node: Examples, Next: Problems, Prev: File format, Up: Top 5 A small tutorial with examples ******************************** @@ -478,7 +483,7 @@ file with a member size of 32MiB. clzip -b 32MiB -S 650MB big_db -File: clzip.info, Node: Problems, Next: Concept Index, Prev: Examples, Up: Top +File: clzip.info, Node: Problems, Next: Concept index, Prev: Examples, Up: Top 6 Reporting Bugs **************** @@ -493,9 +498,9 @@ for all eternity, if not longer. by running `clzip --version'. -File: clzip.info, Node: Concept Index, Prev: Problems, Up: Top +File: clzip.info, Node: Concept index, Prev: Problems, Up: Top -Concept Index +Concept index ************* @@ -504,25 +509,25 @@ Concept Index * algorithm: Algorithm. (line 6) * bugs: Problems. (line 6) * examples: Examples. (line 6) -* file format: File Format. (line 6) +* file format: File format. (line 6) * getting help: Problems. (line 6) * introduction: Introduction. (line 6) -* invoking: Invoking Clzip. (line 6) -* options: Invoking Clzip. (line 6) -* usage: Invoking Clzip. (line 6) -* version: Invoking Clzip. (line 6) +* invoking: Invoking clzip. (line 6) +* options: Invoking clzip. (line 6) +* usage: Invoking clzip. (line 6) +* version: Invoking clzip. (line 6) Tag Table: -Node: Top226 -Node: Introduction920 -Node: Algorithm4811 -Node: Invoking Clzip7335 -Node: File Format12847 -Node: Examples15277 -Node: Problems17238 -Node: Concept Index17764 +Node: Top212 +Node: Introduction914 +Node: Algorithm5096 +Node: Invoking clzip7620 +Node: File format13179 +Node: Examples15658 +Node: Problems17619 +Node: Concept index18145 End Tag Table |