| Extracted from Pike v7.8 release 866 at 2018-07-18.

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Gz
Gz.deflate

# Method Gz.deflate()->create()

Method create

  `void Gz.deflate(int(-9..9)|void level, int|void strategy, int(8..15)|void window_size)`

Description

  This function can also be used to re-initialize a Gz.deflate object so it can be re-used.

Parameter `level`

  Indicates the level of effort spent to make the data compress well. Zero means no packing, 2-3 is considered 'fast', 6 is default and higher is considered 'slow' but gives better packing.

  If the argument is negative, no headers will be emitted. This is needed to produce ZIP-files, as an example. The negative value is then negated, and handled as a positive value.

Parameter `strategy`

  The strategy to be used when compressing the data. One of the following.

  `DEFAULT_STRATEGY` | The default strategy as selected in the zlib library.
  `FILTERED` | This strategy is intented for data created by a filter or predictor and will put more emphasis on huffman encoding and less on LZ string matching. This is between DEFAULT_STRATEGY and HUFFMAN_ONLY.
  `RLE` | This strategy is even closer to the HUFFMAN_ONLY in that it only looks at the latest byte in the window, i.e. a window size of 1 byte is sufficient for decompression. This mode is not available in all zlib versions.
  `HUFFMAN_ONLY` | This strategy will turn of string matching completely, only doing huffman encoding. Window size doesn't matter in this mode and the data can be decompressed with a zero size window.
  `FIXED` | In this mode dynamic huffman codes are disabled, allowing for a simpler decoder for special applications. This mode is not available in all zlib versions.

Parameter `window_size`

  Defines the size of the LZ77 window from 256 bytes to 32768 bytes, expressed as 2^x.