parport_claim_or_block -- claim access to a parallel port device
int parport_claim_or_block (struct pardevice * dev);
pointer to structure representing a device on the port
This behaves like parport_claim, but will block if necessary
to wait for the port to be free. A return value of 1
indicates that it slept; 0 means that it succeeded without
needing to sleep. A negative error code indicates failure.