IOCTL_INTERNAL_PARALLEL_PORT_FREE IOCTL (parallel.h)

The IOCTL_INTERNAL_PARALLEL_PORT_FREE request frees a parallel port. After using a parallel port, a client must free it. Microsoft recommends using the system-supplied PPARALLEL_FREE_ROUTINE callback to free a parallel port because there is no functional advantage to using an IOCTL_INTERNAL_PARALLEL_PORT_FREE request to free the port.

For more information, see Synchronizing the Use of a ParallelPort.

Major code

IRP_MJ_INTERNAL_DEVICE_CONTROL

Input buffer

None.

Input buffer length

None.

Output buffer

None.

Output buffer length

None.

Status block

The Information member is set to zero.

The Status member is set to one of the generic status values returned by internal device control requests for parallel ports.

Requirements

See also

IOCTL_INTERNAL_PARALLEL_PORT_ALLOCATE

PPARALLEL_FREE_ROUTINE