sq.1

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.\" $Log: sq.1,v $
.\" Revision 1.12  2005/04/14 14:38:23  geoff
.\" Update license.
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.\" Revision 1.11  2001/07/25 21:51:46  geoff
.\" Minor license update.
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.\" Revision 1.10  2001/07/23 20:24:04  geoff
.\" Update the copyright and the license.
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.\" Revision 1.9  2000/07/19 23:30:12  geoff
.\" Add a bugs section, and mention gzip instead of compress
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.\" Revision 1.8  1999/01/07 01:57:39  geoff
.\" Update the copyright.
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.TH SQ 1 LOCAL
.SH NAME
sq, unsq \- squeeze or unsqueeze a sorted word list
.SH SYNOPSIS
.B sq
< infile > outfile
.PP
.B unsq
< infile > outfile
.SH DESCRIPTION
.I sq
compresses a sorted list of words (a dictionary). 
For example:
.RS
sort -u /usr/dict/words | sq | gzip -9 > words.sq.Z
.RE
will compress dict by about a factor of 5.
.PP
.I unsq
uncompress the output of
.I sq.
For example:
.RS
gunzip < words.sq.gz | unsq | sort -f -o words
.RE
will uncompress a dictionary compressed with
.I sq.
.P
The squeezing is achieved by eliminating common prefixes, and replacing
them with a single character which encodes the number of characters
shared with the preceding word.
The prefix size is encoded as a single printable character:
0-9 represent 0-9, A-Z represent 10-35, and a-z represent 36-61.
.SH BUGS
.I sq
and
.I unsq
can only handle words of up to 256 characters.
The input must be sorted, and duplicates must be suppressed.
.SH AUTHOR
Mike Wexler
.SH SEE ALSO
compress(1), sort(1).