HP UX 11i v1 I/O Cards manual Ltqdget, Posix 1003.1c kernel threads API package. This routine has

		ZCOM C I/F Library Routines
		LTQDGET (3X)
Threads	This routine may be called from a multi-threaded application using the
Considerations	POSIX (1003.1c) kernel threads API package. This routine has the
	following characteristics when called by a multi-threaded application:
	cancellation point	Thread cancellation can occur when a thread calls this
		routine.
	async-cancel unsafe	The calling thread’s cancelability type must be
		PTHREAD_CANCEL_DEFERRED if cancellation is
		enabled.
	async-signal unsafe	It cannot be called from a signal handler.
	fork unsafe	It cannot be called by a child process after fork(2) but
		before exec(2).
PARAMETERS
	zap	ZCOM address of a terminal from which to get the
		data.
	queue	Terminal data queue number (specifies which data
		queue is to be used).
		0 - Sub-packet holding queue (reserved)
		1 - Data holding queue A
		2 - Data holding queue B
		3 - Data holding queue C
		4 - Data holding queue D
	ibuf (Return Param)	On a successful return, the data is placed into this
		buffer.
	len	Length in bytes of ibuf.
	rlenp (Return Param)	Actual number of bytes returned in ibuf.

NOTES

Normally, the data queue number used should be allocated by ZMON (see the zltqueue man page for how to get a data queue number). There is no queue ownership validation within this routine; it is up to the user to make sure that the queue usage is valid and consistent.

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