xref: /titanic_50/usr/src/man/man9f/bcanput.9f (revision 49f9b365248ee858ee91baa36eab27c5200f6dca)
te
Copyright 1989 AT&T
Copyright (c) 2006, Sun Microsystems, Inc.
All Rights Reserved
The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
BCANPUT 9F "Jan 16, 2006"
NAME
bcanput - test for flow control in specified priority band
SYNOPSIS

#include <sys/stream.h>



int bcanput(queue_t *q, unsigned char pri);
INTERFACE LEVEL

Architecture independent level 1 (DDI/DKI).

PARAMETERS
q

Pointer to the message queue.

pri

Message priority.

DESCRIPTION

The bcanput() function searches through the stream (starting at q) until it finds a queue containing a service routine where the message can be enqueued, or until it reaches the end of the stream. If found, the queue containing the service routine is tested to see if there is room for a message of priority pri in the queue.

If pri is 0, bcanput() is equivalent to a call with canput(9F).

canputnext(q) and bcanputnext(q,pri) should always be used in preference to canput(q\(->q_next) and bcanput(q\(->q_next,pri) respectively.

RETURN VALUES
1

If a message of priority pri can be placed on the queue.

0

If the priority band is full.

CONTEXT

The bcanput() function can be called from user, interrupt, or kernel context.

SEE ALSO

bcanputnext(9F), canput(9F), canputnext(9F), putbq(9F), putnext(9F)

Writing Device Drivers

STREAMS Programming Guide

WARNINGS

Drivers are responsible for both testing a queue with bcanput() and refraining from placing a message on the queue if bcanput() fails.