- zlib push mode channel ?options ...?
This command, part of zlib, adds a compressing or decompressing transformation to channel. The type of transformation is given by the mode, which must be one of compress, decompress, deflate, inflate, gzip, gunzip.
The following options may be used:
- -header dict
- Define gzip header fields, using same rules as zlib gzip. Only used for the gzip transformation.
- -level level
- Define the compression level, using same rules as zlib compress, zlib deflate and zlib gzip. Only used for compressing transformations.
The following fconfigure/chan configure options are added:
- -flush type
- This write-only option causes an immediate operation: it flushes the internal buffers of the transformation. Two types of flush are currently defined: sync flushes empty the buffers but do not make the state restartable, and full flushes empty the buffers and also make the state restartable (at greater performance penalty). For decompressing transformations, there's no difference.
- -checksum number
- This read-only option returns the checksum of the uncompressed data seen so far. The algorithm used is format-dependent.
- -header dict
- This read-only option returns the header dictionary (according to zlib gunzip rules) from a gunzip transformation.