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+COMPACT(1) UNIX Programmer's Manual COMPACT(1)
+
+
+
+NAME
+ compact, uncompact, ccat - compress and uncompress files,
+ and cat them
+
+SYNOPSIS
+ compact [ -v ] [ name ... ]
+ uncompact [ -v ] [ name ... ]
+ ccat [ -v ] [ file ... ]
+
+DESCRIPTION
+ _\bC_\bo_\bm_\bp_\ba_\bc_\bt compresses the named files using an adaptive Huffman
+ code. If no file names are given, the standard input is
+ compacted to the standard output. _\bC_\bo_\bm_\bp_\ba_\bc_\bt operates as an
+ on-line algorithm. Each time a byte is read, it is encoded
+ immediately according to the current prefix code. This code
+ is an optimal Huffman code for the set of frequencies seen
+ so far. It is unnecessary to prepend a decoding tree to the
+ compressed file since the encoder and the decoder start in
+ the same state and stay synchronized. Furthermore, _\bc_\bo_\bm_\bp_\ba_\bc_\bt
+ and _\bu_\bn_\bc_\bo_\bm_\bp_\ba_\bc_\bt can operate as filters. In particular,
+
+ ... | compact | uncompact | ...
+
+ operates as a (very slow) no-op.
+
+ When an argument _\bf_\bi_\bl_\be is given, it is compacted and the
+ resulting file is placed in _\bf_\bi_\bl_\be._\bC; _\bf_\bi_\bl_\be is unlinked. The
+ first two bytes of the compacted file code the fact that the
+ file is compacted. This code is used to prohibit recompac-
+ tion.
+
+ The amount of compression to be expected depends on the type
+ of file being compressed. Typical values of compression
+ are: Text (38%), Pascal Source (43%), C Source (36%) and
+ Binary (19%). These values are the percentages of file
+ bytes reduced.
+
+ _\bU_\bn_\bc_\bo_\bm_\bp_\ba_\bc_\bt restores the original file from a file compressed
+ by _\bc_\bo_\bm_\bp_\ba_\bc_\bt. If no file names are given, the standard input
+ is uncompacted to the standard output.
+
+ _\bC_\bc_\ba_\bt cats the original file from a file compressed by _\bc_\bo_\bm_\b-
+ _\bp_\ba_\bc_\bt, without uncompressing the file (it is just a shell
+ script which directs the uncompacted output to the standard
+ output).
+
+ _\bC_\bo_\bm_\bp_\ba_\bc_\bt, _\bu_\bn_\bc_\bo_\bm_\bp_\ba_\bc_\bt, and _\bc_\bc_\ba_\bt normally do their work
+ silently. If a -v flag is supplied, _\bc_\bo_\bm_\bp_\ba_\bc_\bt will report the
+ compression percentage for each compacted file while _\bu_\bn_\bc_\bo_\bm_\b-
+ _\bp_\ba_\bc_\bt and _\bc_\bc_\ba_\bt will print out the name of each file as
+ they're uncompacted.
+
+
+
+
+Printed 12/6/87 April 29, 1985 1
+
+
+
+
+
+
+COMPACT(1) UNIX Programmer's Manual COMPACT(1)
+
+
+
+RESTRICTION
+ The last segment of the filename must be short enough to
+ allow space for the appended '.C'.
+
+FILES
+ *.C compacted file created by compact, removed by
+ uncompact
+
+SEE ALSO
+ Gallager, Robert G., `Variations on a Theme of Huffman',
+ _\bI._\bE._\bE._\bE. _\bT_\br_\ba_\bn_\bs_\ba_\bc_\bt_\bi_\bo_\bn_\bs _\bo_\bn _\bI_\bn_\bf_\bo_\br_\bm_\ba_\bt_\bi_\bo_\bn _\bT_\bh_\be_\bo_\br_\by, vol. IT-24,
+ no. 6, November 1978, pp. 668 - 674.
+
+AUTHOR
+ Colin L. Mc Master
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+Printed 12/6/87 April 29, 1985 2
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