Xv is underdocumented
The protocol text (draft! still!) stops at XvGetPortAttribute. The five requests past that look like they were added around XFree86 4.0 or so, but they've never been properly documented.
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The protocol text (draft! still!) stops at XvGetPortAttribute. The five requests past that look like they were added around XFree86 4.0 or so, but they've never been properly documented.