Freeze/Melt
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Revision as of 16:12, 28 December 2012
Freeze is a file compression utility used from the command line in Unix-style operating systems. Melt is the corresponding decompressor. It is considered obsolete now in favor of gzip.
A two-pass compression is done with a Lempel-Zev algorithm on the first pass and a dynamic Huffman algorithm on the second. The characteristics of the Huffman table used are added to the file. File attributes, ownership, etc., are preserved, and a .F extension is added. A two-byte magic number is prepended to the file (\037\236 octal for versions 1.x, and \037\237 for later versions).
References
- Man page (in NOAA site, which should know something about freezing!)
- Source code
