STREAMS-UX Programmer's Guide (February 2007)

STREAMS Utilities Supported by HP-UX

Appendix B

208

NAME

rmvq () – Removes a message from a queue.

SYNOPSIS

#include <sys/stream.h>

void *rmvq (queue_t *q, mblk_t *mp);

PARAMETERS

Pointer to the queue from which a message is to be removed.

Pointer to the message targeted for removal.

DESCRIPTION

rmvq() removes a message pointed to by

from the queue specified by

. All flow control parameters for the

queue are appropriately updated. If

is not a valid message pointer for this queue, the results can

unpredictable.

A queue belonging to a module/driver with a synchronization level of SQLVL_NOSYNC may be simultaneously

manipulated by multiple threads. Therefore, the queue specified by

must be frozen by calling freezestr()

before calling insq(), rmvq(), strqget(), and strqset(). A call to unfreezestr() must be made to

unfreeze the queue after the above operations are complete.

RETURN VALUES

None

CONSTRAINTS

rmvq() can be called from thread or interrupt context. Only spinlocks of STREAMS/UX user lock order can be

held across this call.