ref: f2f831eefaa00d6987f8c9a1a22597234b2ce16c
dir: /sys/src/libflate/zlib.h/
/*
* zlib header fields
*/
enum
{
ZlibMeth = 0x0f, /* mask of compression methods */
ZlibDeflate = 0x08,
ZlibCInfo = 0xf0, /* mask of compression aux. info */
ZlibWin32k = 0x70, /* 32k history window */
};