XCB_RANDR_MODE_FLAG_VSYNC_NEGATIVE

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
extern (C)
alias XCB_RANDR_MODE_FLAG_VSYNC_NEGATIVE = xcb_randr_mode_flag_t.XCB_RANDR_MODE_FLAG_VSYNC_NEGATIVE

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