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+.Dd November 8, 2018
+.Dt COMPRESS 3
+.Os
+.
+.Sh NAME
+.Nm compress ,
+.Nm compress2 ,
+.Nm compressBound
+.Nd compress source buffer into destination buffer
+.
+.Sh LIBRARY
+.Lb libz
+.
+.Sh SYNOPSIS
+.In zlib.h
+.
+.Ft int
+.Fo compress
+.Fa "Bytef *dest"
+.Fa "uLongf *destLen"
+.Fa "const Bytef *source"
+.Fa "uLong sourceLen"
+.Fc
+.
+.Ft int
+.Fo compress2
+.Fa "Bytef *dest"
+.Fa "uLongf *destLen"
+.Fa "const Bytef *source"
+.Fa "uLong sourceLen"
+.Fa "int level"
+.Fc
+.
+.Ft uLong
+.Fn compressBound "uLong sourceLen"
+.
+.Sh DESCRIPTION
+Compresses the source buffer into the destination buffer.
+.Fa sourceLen
+is the byte length of the source buffer.
+Upon entry,
+.Fa destLen
+is the total size of the destination buffer,
+which must be at least the value returned by
+.Fn compressBound sourceLen .
+Upon exit,
+.Fa destLen
+is the actual size of the compressed data.
+.
+.Pp
+.Fn compress
+is equivalent to
+.Fn compress2
+with a
+.Fa level
+parameter of
+.Dv Z_DEFAULT_COMPRESSION .
+.
+.Pp
+.Fn compressBound
+returns an upper bound on the compressed size after
+.Fn compress
+or
+.Fn compress2
+on
+.Fa sourceLen
+bytes.
+It would be used before a
+.Fn compress
+or
+.Fn compress2
+call to allocate the destination buffer.
+.
+.Sh RETURN VALUES
+.Fn compress
+and
+.Fn compress2
+return
+.Dv Z_OK
+on success,
+.Dv Z_MEM_ERROR
+if there was not enough memory,
+.Dv Z_BUF_ERROR
+if there was not enough room in the output buffer,
+.Dv Z_STREAM_ERROR
+if the
+.Fa level
+parameter is invalid.