FILTERS(2) FILTERS(2)
NAME
deflate, inflate - data processing modules
SYNOPSIS
include "filter.m";
deflate := load Filter "/dis/lib/deflate.dis";
inflate := load Filter "/dis/lib/inflate.dis";
DESCRIPTION
This page describes the currently implemented data-
processing filters conforming to the Filter module inter-
face. For details of the interface, see filter(2).
deflate Deflate implements gzip-compatible stream compres-
sion. The param string argument to start can con-
tain one or more of the following option charac-
ters:
`d' Enable debugging output. Each line of debug-
ging output is provided in an Rq.Info mes-
sage.
`v' Enable verbose mode. Each line of verbose
output is provided in an Rq.Info message.
`h' Add a gzip header and footer to the data.
With this flag, the data after filtering will
be in exactly the same format as a gzip file,
with accompanying checksum.
`0' to `9'
Specifies the level of compression to be used
(9 highest). See gzip(1).
inflate Inflate performs the inverse operation to deflate.
If the param argument to start begins with the
character `h' then the input to the filter is
assumed to be in the standard gzip file format;
the output will be checked for integrity. While
processing, the Rq.Info message is used to trans-
mit some information; the type of information is
determined by the first word of msg, as follows:
file The rest of msg (after a following space) is
the name of the original filename before com-
pression.
mtime
The rest of msg (after a following space) is
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FILTERS(2) FILTERS(2)
the modification time of the original file
before compression.
SOURCE
/appl/lib/deflate.b
/appl/lib/inflate.b
SEE ALSO
gzip(1), filter(2)
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