'\" te
.\" Copyright (c) 2004, Sun Microsystems, Inc.  All Rights Reserved
.TH mcopyout 9F "9 June 2004" "SunOS 5.11" "Kernel Functions for Drivers"
.SH NAME
mcopyout \- Convert an M_IOCTL or M_IOCDATA message to an M_COPYOUT
.SH SYNOPSIS
.LP
.nf
#include <sys/stream.h>
#include <sys/strsun.h>

\fBvoid\fR \fBmcopyout\fR(\fBmblk_t *\fR\fImp\fR, \fBvoid *\fR\fIprivate\fR, \fBsize_t\fR \fIsize\fR, \fBvoid *\fR\fIuseraddr\fR,
      \fBmblk_t *\fR\fIdp\fR);
.fi

.SH INTERFACE LEVEL
.sp
.LP
Solaris DDI specific (Solaris DDI).
.SH PARAMETERS
.sp
.ne 2
.mk
.na
\fB\fImp\fR\fR
.ad
.RS 12n
.rt  
M_IOCTL or M_IOCDATA message.
.RE

.sp
.ne 2
.mk
.na
\fB\fIprivate\fR\fR
.ad
.RS 12n
.rt  
Value to set the cq_private field of the \fBcopyreq\fR(9S) to.
.RE

.sp
.ne 2
.mk
.na
\fB\fIsize\fR\fR
.ad
.RS 12n
.rt  
Value to set the cq_size field of the \fBcopyreq\fR(9S) to.
.RE

.sp
.ne 2
.mk
.na
\fB\fIuseraddr\fR\fR
.ad
.RS 12n
.rt  
Optionally, the value to set the cq_addr field of the \fBcopyreq\fR(9S) to.
.RE

.sp
.ne 2
.mk
.na
\fB\fIdp\fR\fR
.ad
.RS 12n
.rt  
Optionally, the payload to copy out.
.RE

.SH DESCRIPTION
.sp
.LP
The \fBmcopyout()\fR function converts an M_IOCTL or M_IOCDATA message into an M_COPYOUT message using the supplied arguments.
.sp
.LP
To convert the message, \fBmcopyout()\fR changes the message type to M_COPYOUT, and its payload from a \fBiocblk\fR(9S) to a \fBcopyreq\fR(9S). Since the \fBiocblk\fR(9S) and \fBcopyreq\fR(9S) are designed to overlay one another, the only fields which must be updated are \fBcq_private\fR, \fBcq_size\fR, and \fBcq_addr\fR, which are set to the supplied values. If \fIuseraddr\fR is passed as NULL, the M_IOCTL must be transparent and \fBcq_addr\fR is assigned the pointer-sized quantity found at \fBmp->b_cont->b_rptr\fR. 
.sp
.LP
If \fIdp\fR is not NULL, any trailing message blocks associated with \fImp\fR are freed, \fBmp->b_cont\fR is reset to \fIdp\fR and \fBdp->b_wptr\fR is set to \fBdp->b_rptr + size\fR. Otherwise, any trailing message blocks are unaffected.
.SH RETURN VALUES
.sp
.LP
None.
.SH CONTEXT
.sp
.LP
This function can be called from user, kernel or interrupt context.
.SH SEE ALSO
.sp
.LP
\fBmcopyin\fR(9F), \fBcopyreq\fR(9S), \fBiocblk\fR(9S)
.sp
.LP
\fISTREAMS Programming Guide\fR