2.
tool The
Unix program "compress", now largely
Unix compress was written in
C by Joseph M. Orost, James
A. Woods et al., and was widely circulated via
Usenet. It
files with the suffix ".Z".
Compress uses variable length codes. Initially, nine-bit
codes are output until they are all used. When this occurs,
ten-bit codes are used and so on, until an
implementation-dependent maximum is reached.
After every 10
kilobytes of input the compression ratio is
checked. If it is decreasing then the entire string table is
discarded and information is collected from scratch.