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4 .\" Copyright (c) 1997, 2003, 2004 Matthew R. Green
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35 .Nd compression/decompression tool using Lempel-Ziv coding (LZ77)
63 program compresses and decompresses files using Lempel-Ziv coding
69 will compress from standard input, or decompress to standard output.
70 When in compression mode, each
72 will be replaced with another file with the suffix, set by the
74 option, added, if possible.
75 In decompression mode, each
77 will be checked for existence, as will the file with the suffix
97 is also capable of decompressing files compressed using
102 The following options are available:
103 .Bl -tag -width XXrXXXrecursiveX
113 These options change the compression level used, with the
115 option being the fastest, with less compression, and the
117 option being the slowest, with optimal compression.
118 The default compression level is 6.
119 .It Fl c , -stdout , -to-stdout
120 This option specifies that output will go to the standard output
121 stream, leaving files intact.
122 .It Fl d , -decompress , -uncompress
123 This option selects decompression rather than compression.
125 This option turns on force mode.
126 This allows files with multiple links, overwriting of pre-existing
127 files, reading from or writing to a terminal, and when combined
130 option, allowing non-compressed data to pass through unchanged.
132 This option prints a usage summary and exits.
134 Keep (don't delete) input files during compression
137 This option displays information about the file's compressed and
138 uncompressed size, ratio, uncompressed name.
141 option, it also displays the compression method, CRC, data and time
142 embedded in the file.
144 This option causes the stored filename in the input file to be used
147 This option stops the filename from being stored in the output
150 With this option, no warnings or errors are printed.
151 .It Fl r , -recursive
152 This option is used to
154 the files in a directory tree individually, using the
157 .It Fl S Ar suffix , Fl -suffix Ar suffix
158 This option changes the default suffix from .gz to
161 This option will test compressed files for integrity.
163 This option prints the version of the
167 This option turns on verbose mode, which prints the compression
168 ratio for each file compressed.
171 If the environment variable
173 is set, it is parsed as a white-space separated list of options
174 handled before any options on the command line.
175 Options on the command line will override anything in
185 program was originally written by Jean-loup Gailly, licensed under
186 the GNU Public Licence.
187 Matthew R. Green wrote a simple front end for
189 distribution media, based on the freely re-distributable zlib library.
190 It was enhanced to be mostly feature-compatible with the original
196 This manual documents
201 This implementation of
204 .An Matthew R. Green Aq mrg@eterna.com.au .