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diff --git a/Build/source/utils/lzma-utils/src/lzma/lzma.1 b/Build/source/utils/lzma-utils/src/lzma/lzma.1 deleted file mode 100644 index dfcbac329b7..00000000000 --- a/Build/source/utils/lzma-utils/src/lzma/lzma.1 +++ /dev/null @@ -1,228 +0,0 @@ -.TH LZMA 1 "23 Dec 2005" "LZMA utils" - -.SH NAME -lzma, unlzma, lzcat \- LZMA compression and decompression tool - -.SH SYNOPSIS -.B lzma -.RB [ \-123456789cdefhkLqtvV "] [" \-S -.IR suffix "] [" "filenames ..." ] -.br -.B unlzma -.RB [ \-cfhkLqtvV "] [" \-S -.IR suffix "] [" "filenames ..." ] -.br -.B lzcat -.RB [ \-fhLqV ] -.RI [ "filenames ..." ] - -.SH DESCRIPTION -LZMA (Lempel-Ziv-Markov chain-Algorithm) is an improved version of -famous LZ77 compression algorithm. It was improved in way of maximum -increasing of compression ratio, keeping high decompression speed and -low memory requirements for decompressing. -.PP -.B lzma -command line tool has a similar interface to -.BR gzip (1) -and -.BR bzip2 (1) -and is intended to make use of LZMA compression easy for the users who -are already familiar with gzip and bzip2. -.PP -In this manual -.B lzma -is compared mostly to bzip2 because that is currently one of the most -widely used free software to compress tar files made for distribution. -Comparing lzma to gzip is not practical because neither lzma nor bzip2 -can compete with gzip in compression speed. On the other hand the -compression ratio of gzip is worse than of lzma and bzip2. -.PP -.B lzma -provides notably better compression ratio than bzip2 especially with -files having other than plain text content. The other advantage of -.B lzma -is fast decompression which is many times quicker than bzip2. The major -disadvantage is that achieving the highest compression ratios requires -extensive amount of system resources, both CPU time and RAM. Also -software to handle LZMA compressed files is not installed by default on -most distributions. -.PP -When compressing or decompressing with -.BR lzma , -the new file will have the same ownership information, permissions and -timestamps as the original file. However the this information is not -stored into the compressed file like gzip does. - -.SH STREAMED VS. NON-STREAMED -LZMA files can be either streamed or non-streamed. Non-streamed files -are created only when the size of the file being compressed is known. In -practice this means that the source file must be a regular file. In -other words, if compressing from the standard input or from a named pipe -(fifo) the compressed file will always be streamed. -.PP -Both streamed and non-streamed files are compressed identically; the -only differences are found from the beginnings and ends of LZMA -compressed files: Non-streamed files contain the uncompressed size of -the file in the LZMA file header; streamed files have uncompressed size -marked as unknown. To know where to stop decoding, streamed files have a -special End Of Stream marker at the end of the LZMA file. The EOS marker -makes streamed files five or six bytes bigger than non-streamed. -.PP -So in practice creating non-streamed files has two advantages: 1) the -compressed file is a few bytes smaller and 2) the uncompressed size of -the file can be checked without decompressing the file. To view the data -stored in the LZMA header use -.BR lzmainfo (1). - -.SH OPTIONS -Short options can be grouped like -.BR \-cd. -.TP -.B \-c \-\-stdout \-\-to\-stdout -The output is written to the standard output. The original files are kept -unchanged. When compressing to the standard output there can be only one -input file. This option is implied when input is read from the standard -input or the script is invoked as -.BR lzcat . -.TP -.B \-d \-\-decompress \-\-uncompress -Force decompression regardless of the invocation name. This the default -when called as -.B unlzma -or -.BR lzcat . -.TP -.B \-f \-\-force -Force compression or decompression even if source file is a symlink, -target exists, or target is a terminal. In contrast to gzip and bzip2, -if input data is not in LZMA format, \-\-force does not make lzma -behave like -.BR cat . -.B lzma -never prompts if target file should be overwritten; existing files are -skipped or, in case of -.BR \-\-force , -overwritten. -.TP -.B \-h \-\-help -Show a summary of supported options and quit. -.TP -.B \-k \-\-keep -Do not delete the input files after compression or decompression. -.TP -.B \-L \-\-license -Show licensing information of -.BR lzma . -.TP -.B \-q \-\-quiet -Suppress all warnings. You can still check the exit status to detect if -a warning had been shown. -.TP -.BI "\-S \-\-suffix " .suf -Use -.I .suf -instead of the default -.BR .lzma . -A null suffix forces unlzma to decompress all the given files -regardless of the filename suffix. -.TP -.B \-t \-\-test -Check the integrity of the compressed file(s). Without -.B \-\-verbose -no output is produced if no errors are found. -.TP -.B \-v \-\-verbose -Show the filename and percentage reduction of each processes file. -.TP -.B \-V \-\-version -Show the version number of -.BR lzma . -.TP -.B \-z \-\-compress -Force compression regardless of the invocation name. -.TP -.BR \-1 " .. " \-9 -Set the compression ratio. See the next chapter for detailed -information. These options have no effect when decompressing. -.TP -.B \-\-fast -Alias to -.BR \-1 . -.TP -.B \-\-best -Alias to -.BR \-9 . - -.SH COMPRESSION OPTIONS AND MEMORY USAGE -The compression options of -.B lzma -are divided to two groups. The first two -.RB ( \-1 " and " \-2 ) -are designed for fast compression speed. -.BR \-3 " .. " \-9 -provide good to excellent compression ratio but require more CPU time -and system memory. -.PP -For relatively fast compression with medium compression ratio -.B \-1 -is the recommended setting. It's faster than 'bzip2 \-\-fast' and -usually creates smaller files than 'bzip2 \-\-best'. -.B \-2 -makes somewhat smaller files but doubles the compression time close to -what 'bzip2 \-\-best' takes. -.PP -Generally for excellent compression ratio, acceptable compression time -and memory requirements (about 83 MB for compression, 9 MB for -decompression) you should use -.B \-7 -which is also the default. -.B \-8 -and -.B \-9 -will give some gain especially with bigger files (>=tens of megabytes) -but also increase the CPU and memory requirements dramatically. See the -table below for memory requirements of different compression settings. -.PP - Flag Compress usage Decompress usage - -1 2 MB 1 MB - -2 12 MB 2 MB - -3 12 MB 1 MB - -4 16 MB 2 MB - -5 26 MB 3 MB - -6 45 MB 5 MB - -7 83 MB 9 MB - -8 159 MB 17 MB - -9 311 MB 33 MB - -.SH DIAGNOSTICS -Exit status: -.br -.B 0 -\- Everything OK. -.br -.B 1 -\- An error occurred. -.br -.B 2 -\- Something worth a warning happened but no errors. - -.SH AUTHORS -The LZMA algorithm and the implementation used in LZMA utils was -developed by Igor Pavlov. The original code is available in LZMA SDK -which can be found from http://7-zip.org/sdk.html . -.PP -.B lzma -command line tool was written by Ville Koskinen. -http://tukaani.org/lzma/ -.PP -This manual page is inspired by manual pages of -.B gzip -and -.BR bzip2 . - -.SH SEE ALSO -.BR lzmadec (1), -.BR lzmainfo (1), -.BR gzip (1), -.BR bzip2 (1) |