xref: /titanic_51/usr/src/man/man9f/dupmsg.9f (revision c10c16dec587a0662068f6e2991c29ed3a9db943)
te
Copyright 1989 AT&T
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]
dupmsg 9F "11 Apr 1991" "SunOS 5.11" "Kernel Functions for Drivers"
NAME
dupmsg - duplicate a message
SYNOPSIS

#include <sys/stream.h>



mblk_t *dupmsg(mblk_t *mp);
INTERFACE LEVEL

Architecture independent level 1 (DDI/DKI).

PARAMETERS

mp

Pointer to the message.

DESCRIPTION

dupmsg() forms a new message by copying the message block descriptors pointed to by mp and linking them. dupb(9F) is called for each message block. The data blocks themselves are not duplicated.

RETURN VALUES

If successful, dupmsg() returns a pointer to the new message block. Otherwise, it returns a NULL pointer. A return value of NULL indicates either memory depletion or the data block reference count, db_ref (see datab(9S)), has reached a limit (255). See dupb(9F).

CONTEXT

dupmsg() can be called from user, kernel, or interrupt context.

EXAMPLES

Example 1 Using dupmsg()

See copyb(9F) for an example using dupmsg().

SEE ALSO

copyb(9F), copymsg(9F), dupb(9F), datab(9S)

Writing Device Drivers

STREAMS Programming Guide