__GLX_DRAWPIXELS_CMD_DISPATCH_HDR_SIZE

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
version(linux)
extern (C)
enum __GLX_DRAWPIXELS_CMD_DISPATCH_HDR_SIZE = __GLX_PIXEL_HDR_SIZE + __GLX_DRAWPIXELS_HDR_SIZE;

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