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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 This option displays information about the file's compressed and
135 uncompressed size, ratio, uncompressed name.
138 option, it also displays the compression method, CRC, data and time
139 embedded in the file.
141 This option causes the stored filename in the input file to be used
144 This option stops the filename from being stored in the output
147 With this option, no warnings or errors are printed.
148 .It Fl r , -recursive
149 This option is used to
151 the files in a directory tree individually, using the
154 .It Fl S Ar suffix , Fl -suffix Ar suffix
155 This option changes the default suffix from .gz to
158 This option will test compressed files for integrity.
160 This option prints the version of the
164 This option turns on verbose mode, which prints the compression
165 ratio for each file compressed.
168 If the environment variable
170 is set, it is parsed as a white-space separated list of options
171 handled before any options on the command line.
172 Options on the command line will override anything in
182 program was originally written by Jean-loup Gailly, licensed under
183 the GNU Public Licence.
184 Matthew R. Green wrote a simple front end for
186 distribution media, based on the freely re-distributable zlib library.
187 It was enhanced to be mostly feature-compatible with the original
193 This manual documents
198 This implementation of
201 .An Matthew R. Green Aq mrg@eterna.com.au .