MIOCPULLUP(9F) Kernel Functions for Drivers MIOCPULLUP(9F)

NAME

miocpullup - Prepare the payload of an M_IOCTL message for access

SYNOPSIS

#include <sys/stream.h>
#include <sys/strsun.h>


int miocpullup(mblk_t *mp, size_t size);

INTERFACE LEVEL

illumos DDI specific (illumos DDI).

PARAMETERS

mp
M_IOCTL message.


size
Number of bytes to prepare.

DESCRIPTION

The miocpullup() function prepares the payload of the specified
M_IOCTL message for access by ensuring that it consists of at least
size bytes of data.


If the M_IOCTL message is transparent, or its total payload is less
than size bytes, an error is returned. Otherwise, the payload is
concatenated as necessary to provide contiguous access to at least
size bytes of data. As a special case, if size is zero, miocpullup()
returns successfully, even if no payload exists.

RETURN VALUES

Zero is returned on success. Otherwise an errno value is returned
indicating the problem.

CONTEXT

This function can be called from user, kernel or interrupt context.

SEE ALSO

STREAMS Programming Guide

June 9, 2004 MIOCPULLUP(9F)