1 compress_ascii, ca   new_compress_ascii, nca    expand_ascii, xa
 2 
 3 
 4 Syntax:   compress_ascii table path {-control args}
 5           new_compress_ascii path {-control args}
 6           expand_ascii path {-control args}
 7 
 8 
 9 Function: Compresses and expands ASCII segments to save storage.
10 
11 
12 Arguments:
13 table
14    For use with compress_ascii only, is the pathname of a table
15    specifying the encoding to use for compression.  The user may
16    create his own table using the make_compression_table command, or
17    he may use the table in >am>compression_table.
18 path
19    is the pathname of the segment to compress or expand.  The suffix
20    ".ca" is optional.  The compressed segment is given the same name
21    as the original segment, with the ".ca" suffix added.  If
22    expanding, the ".ca" suffix is removed.  The output segment is
23    placed in the working directory.
24 
25 
26 Control Arguments:
27 -replace, -rp
28    specifies that the compressed or expanded segment is to replace
29    the original, rather than being placed in the working directory.
30    The name of the segment will be changed to add or remove the ".ca"
31    suffix as required.
32 -brief, -bf
33    inhibits printing of a message indicating the old and new lengths
34    of the segments.
35 
36 
37 Notes: The two commands, compress_ascii, and new_compress_ascii, are
38 different in the manner in which they compress segments.
39 compress_ascii requires a compression table, and will compress any
40 ASCII segment regardless of size.  new_compress_ascii requires no
41 compression table, and, for most text, results in a smaller
42 segment than that produced by compress_ascii.  However, it is
43 slower and will not work on segments containing more than
44 about 3500 unique "words" longer than one character (duplicate words
45 not included).  An error message will be printed if the segment
46 does not satisfy this requirement.  All compressed segments are
47 self contained--no reference to the compression table is required
48 to use expand_ascii, which will work on a segment created by
49 either command.  The only difference is that segments produced by
50 new_compress_ascii are much quicker to expand than segments
51 produced by compress_ascii.