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diff --git a/doc/lzip.info b/doc/lzip.info index 9379eb3..e61550e 100644 --- a/doc/lzip.info +++ b/doc/lzip.info @@ -11,7 +11,7 @@ File: lzip.info, Node: Top, Next: Introduction, Up: (dir) Lzip Manual *********** -This manual is for Lzip (version 1.13, 24 February 2012). +This manual is for Lzip (version 1.14, 17 February 2013). * Menu: @@ -24,7 +24,7 @@ This manual is for Lzip (version 1.13, 24 February 2012). * Concept Index:: Index of concepts - Copyright (C) 2008, 2009, 2010, 2011, 2012 Antonio Diaz Diaz. + Copyright (C) 2008, 2009, 2010, 2011, 2012, 2013 Antonio Diaz Diaz. This manual is free documentation: you have unlimited permission to copy, distribute and modify it. @@ -67,12 +67,16 @@ split the compressed output in volumes of a given size, even when reading from standard input. This allows the direct creation of multivolume compressed tar archives. - The amount of memory required for compression is about 5 MiB plus 1 -or 2 times the dictionary size limit (1 if input file size is less than -dictionary size limit, else 2) plus 8 times the dictionary size really -used. The option `-0' is special and only requires about 1.5 MiB at -most. The amount of memory required for decompression is only a few tens -of KiB larger than the dictionary size really used. + Lzip is able to compress and decompress streams of unlimited size by +automatically creating multi-member output. The members so created are +large (about 2^60 bytes each). + + The amount of memory required for compression is about 1 or 2 times +the dictionary size limit (1 if input file size is less than dictionary +size limit, else 2) plus 9 times the dictionary size really used. The +option `-0' is special and only requires about 1.5 MiB at most. The +amount of memory required for decompression is only a few tens of KiB +larger than the dictionary size really used. Lzip will automatically use the smallest possible dictionary size without exceeding the given limit. Keep in mind that the decompression @@ -325,7 +329,12 @@ File: lzip.info, Node: File Format, Next: Examples, Prev: Invoking Lzip, Up: 4 File Format ************* -In the diagram below, a box like this: +Perfection is reached, not when there is no longer anything to add, but +when there is no longer anything to take away. +-- Antoine de Saint-Exupery + + + In the diagram below, a box like this: +---+ | | <-- the vertical bars might be missing +---+ @@ -354,15 +363,18 @@ additional information before, between, or after them. "LZIP". `VN (version number, 1 byte)' - Just in case something needs to be modified in the future. Valid - values are 0 and 1. Version 0 files are deprecated. They can - contain only one member and lack the `Member size' field. + Just in case something needs to be modified in the future. 1 for + now. `DS (coded dictionary size, 1 byte)' - Bits 4-0 contain the base 2 logarithm of the base dictionary size. - Bits 7-5 contain the number of "wedges" to substract from the base - dictionary size to obtain the dictionary size. The size of a wedge - is (base dictionary size / 16). + Lzip divides the distance between any two powers of 2 into 8 + equally spaced intervals, named "wedges". The dictionary size is + calculated by taking a power of 2 (the base size) and substracting + from it a number of wedges between 0 and 7. The size of a wedge is + (base_size / 16). + Bits 4-0 contain the base 2 logarithm of the base size (12 to 29). + Bits 7-5 contain the number of wedges (0 to 7) to substract from + the base size to obtain the dictionary size. Valid values for dictionary size range from 4KiB to 512MiB. `Lzma stream' @@ -376,9 +388,9 @@ additional information before, between, or after them. Size of the uncompressed original data. `Member size (8 bytes)' - Total size of the member, including header and trailer. This - facilitates safe recovery of undamaged members from multi-member - files. + Total size of the member, including header and trailer. This field + acts as a distributed index, and facilitates safe recovery of + undamaged members from multi-member files. @@ -493,13 +505,13 @@ Concept Index Tag Table: Node: Top224 -Node: Introduction919 -Node: Algorithm4420 -Node: Invoking Lzip6938 -Node: File Format12290 -Node: Examples14283 -Node: Problems16230 -Node: Concept Index16752 +Node: Introduction925 +Node: Algorithm4590 +Node: Invoking Lzip7108 +Node: File Format12460 +Node: Examples14767 +Node: Problems16714 +Node: Concept Index17236 End Tag Table |