'\" te
.\" Copyright (c) 2004, 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.
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.TH MIOCPULLUP 9F "Jun 9, 2004"
.SH NAME
miocpullup \- Prepare the payload of an M_IOCTL message for access
.SH SYNOPSIS
.nf
#include <sys/stream.h>
#include <sys/strsun.h>



\fBint\fR \fBmiocpullup\fR(\fBmblk_t *\fR\fImp\fR, \fBsize_t\fR \fIsize\fR);
.fi

.SH INTERFACE LEVEL
illumos DDI specific (illumos DDI).
.SH PARAMETERS
.ne 2
.na
\fB\fImp\fR\fR
.ad
.RS 8n
M_IOCTL message.
.RE

.sp
.ne 2
.na
\fB\fIsize\fR\fR
.ad
.RS 8n
Number of bytes to prepare.
.RE

.SH DESCRIPTION
The \fBmiocpullup()\fR function prepares the payload of the specified M_IOCTL
message for access by ensuring that it consists of at least \fIsize\fR bytes of
data.
.sp
.LP
If the M_IOCTL message is transparent, or its total payload is less than
\fIsize\fR bytes, an error is returned.  Otherwise, the payload is concatenated
as necessary to provide contiguous access to at least \fIsize\fR bytes of data.
As a special case, if \fIsize\fR is zero, \fBmiocpullup()\fR returns
successfully, even if no payload exists.
.SH RETURN VALUES
Zero is returned on success. Otherwise an errno value is returned indicating
the problem.
.SH CONTEXT
This function can be called from user, kernel or interrupt context.
.SH SEE ALSO
\fISTREAMS Programming Guide\fR