STREAMS-UX Programmer's Guide (February 2007)

STREAMS Utilities Supported by HP-UX

Appendix B

205

NAME

qsize () – Returns the number of messages in a queue.

SYNOPSIS

#include <sys/stream.h>

int qsize (queue_t *q);

PARAMETERS

Pointer to queue.

RETURN VALUES

This function returns the number of messages in the specified queue. If the message queue is empty, 0 is

returned.

CONSTRAINTS

qsize() can be called from thread or interrupt context. Spinlocks of STREAMS/UX user lock order can be

held across calls to this function for modules/drivers configured with a synchronization level of

SQLVL_NOSYNC. For modules/drivers configured with any other synchronization level, spinlocks that are not

necessarily of the STREAMS/UX user lock order, can be held across calls to this function.