The Linux SCSI programming HOWTO: Ioctl Functions 12. Ioctl FunctionsThere are two ioctl functions available:ioctl(fd, SG_SET_TIMEOUT, &Timeout); sets the timeout value to Timeout * 10 milliseconds. Timeout has to be declared as int.ioctl(fd, SG_GET_TIMEOUT, &Timeout); gets the current timeout value. Timeout has to be declared as int.