IOC_OUT
if (cmd & (IOC_IN | IOC_OUT)) {
} else if (cmd & IOC_OUT) {
if (cmd & IOC_OUT)
if ((cmd & ioctl->cmd & IOC_OUT) == 0)
} else if ((com&IOC_OUT) && size)
if (error == 0 && (com&IOC_OUT) && size)
#define O_DIOCGDINFO _IOC(IOC_OUT, 'd', 101, O_disklabel)
#define IOC_INOUT (IOC_IN|IOC_OUT)
#define _IOR(g,n,t) _IOC(IOC_OUT, (g), (n), sizeof(t))
if (cmd & IOC_OUT)