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Compress - How small can a file before it will create the .Z
Post 28350 by Kelam_Magnus on Tuesday 17th of September 2002 12:19:21 PM
09-17-2002
I agree that the size doesn't matter 
(ha!).
If you have a file with the value of PI. I believe that it doesn't have any repeating chars or blanks. So it probably wouldn't be compressed at all. However, a file with six bytes that has a space in the middle would be compressed.
I might be somewhat incorrect, but I think most of the compression algorithm has to do with repeating of chars and patterns and blanks, more than anything else.
(ha!).If you have a file with the value of PI. I believe that it doesn't have any repeating chars or blanks. So it probably wouldn't be compressed at all. However, a file with six bytes that has a space in the middle would be compressed.
I might be somewhat incorrect, but I think most of the compression algorithm has to do with repeating of chars and patterns and blanks, more than anything else.
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LEARN ABOUT ULTRIX
compact
compact(1) General Commands Manual compact(1) Name compact, uncompact, ccat - compress and uncompress files, and cat them Syntax compact [name...] uncompact [name...] ccat [file...] Description The command compresses the named files using an adaptive Huffman code. If no file names are given, the standard input is compacted to the standard output. The command operates as an on-line algorithm. Each time a byte is read, it is encoded immediately according to the cur- rent 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, and can operate as filters. In particular, ... | compact | uncompact | ... operates as a (very slow) no-op. When an argument file is given, it is compacted and the resulting file is placed in file.C; file is unlinked. The first two bytes of the compacted file code the fact that the file is compacted. This code is used to prohibit recompaction. The amount of compression to be expected depends on the type of file being compressed. Typical values of compression are: Text (38%), Pas- cal Source (43%), C Source (36%) and Binary (19%). These values are the percentages of file bytes reduced. The command restores the original file from a file compressed by If no file names are given, the standard input is uncompacted to the stan- dard output. The command cats the original file from a file compressed by without uncompressing the file. The command is present only for compatibility. In general, the command runs faster and gives better compression. Restrictions The last segment of the file name must contain fewer than thirteen characters to allow space for the appended '.C'. Files compacted file created by compact, removed by uncompact See Also compress(1) compact(1)