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.Dd January 15, 2017
.Dt DEFLATETUNE 3
.Os
.
.Sh NAME
.Nm deflateTune
.Nd fine tune compression parameters
.
.Sh LIBRARY
.Lb libz
.
.Sh SYNOPSIS
.In zlib.h
.Ft int
.Fo deflateTune
.Fa "z_streamp strm"
.Fa "int good_length"
.Fa "int max_lazy"
.Fa "int nice_length"
.Fa "int max_chain"
.Fc
.
.Sh DESCRIPTION
Fine tune deflate's internal compression parameters.
This should only be used
by someone who understands the algorithm
used by zlib's deflate
for searching for the best matching string,
and even then only by the most fanatic optimizer
trying to squeeze out the last compressed bit
for their specific input data.
Read the
.Pa deflate.c
source code for the meaning of the
.Fa max_lazy ,
.Fa good_length ,
.Fa nice_length ,
and
.Fa max_chain
parameters.
.
.Pp
.Fn deflateTune
can be called after
.Xr deflateInit 3
or
.Xr deflateInit2 3 .
.
.Sh RETURN VALUES
.Fn deflateTune
returns
.Dv Z_OK
on success,
or
.Dv Z_STREAM_ERROR
for an invalid deflate stream.
.
.Sh SEE ALSO
.Xr deflateInit 3 ,
.Xr deflateInit2 3
.
.Sh HISTORY
This manual page was converted from
.In zlib.h
to mdoc format by
.An June McEnroe Aq Mt june@causal.agency .
.
.Sh AUTHORS
.An Jean-loup Gailly Aq Mt jloup@gzip.org
.An Mark Adler Aq Mt madler@alumni.caltech.edu