int _xcb_out_init(_xcb_out *out);
void _xcb_out_destroy(_xcb_out *out);
-int _xcb_out_write(XCBConnection *c, struct iovec **vector, int *count);
int _xcb_out_send(XCBConnection *c, struct iovec **vector, int *count);
int _xcb_out_flush_to(XCBConnection *c, unsigned int request);