xref: /illumos-gate/usr/src/man/man9f/miocpullup.9f (revision 3184921a)
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MIOCPULLUP 9F "Jun 9, 2004"
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