queue

canput(9r)																canput(9r)

NAME

       canput - STREAMS: Tests for room in a message queue

SYNOPSIS

       #include <sys/stream.h>

       int canput(
	       queue_t *message_queue );

ARGUMENTS

       Specifies a pointer to the message queue. The typedef queue_t is an alternate name for struct queue_entry *.

DESCRIPTION

       The  canput interface searches through the stream (starting at the message queue identified by the message_queue argument) until it finds a
       queue that contains a service interface where the message can be enqueued or until it reaches the end of the stream.   If  canput  finds  a
       service	interface  in  a  queue, it tests the queue to determine if there is space in the queue to accommodate a message.  If the queue is
       full, canput sets the q_flag member of the queue_entry structure pointer (the message queue) to the  constant  QWANTW  to  back-enable  the
       caller's service interface.

NOTES

       You are responsible for both testing a queue with canput and not placing a message on the queue if canput fails.

RETURN VALUES

       The canput interface returns a value of 1 if the message queue is not full. It returns the value zero(0) if the message queue is full.

SEE ALSO

       Kernel Interfaces: bcanput(9r), putbq(9r), putnext(9r)

       Programmer's Guide: STREAMS

																	canput(9r)