Tribblix: manual page: miocack.9f

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

NAME

miocack - Positively acknowledge an M_IOCTL message

SYNOPSIS

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

void miocack(queue_t *wq, mblk_t *mp, intcount, int rval);

INTERFACE LEVEL

illumos DDI specific (illumos DDI).

PARAMETERS

wq
Write queue associated with the read queue to send the
M_IOCACK on.

mp
M_IOCTL message.

count
Value to set the ioc_count of the iocblk(9S) to.

rval
Value to set the ioc_rval of the iocblk(9S) to.

DESCRIPTION

The miocack() function converts an M_IOCTL message into a M_IOCACK
message and sends the resulting message upstream.

To convert the message, miocack() changes the message type to
M_IOCACK, sets the 'ioc_count' and 'ioc_rval' members of the
iocblk(9S) associated with mp to the passed-in values, and clears the
'ioc_error' field. If the caller specifies a non-zero value for
count, it is expected that the caller has already set 'mp->b_cont'
field to point to a message block with a length of at least count
bytes.

Callers that only need to perform the message conversion, or need to
perform additional steps between the conversion and the sending
of the M_IOCACK should use mioc2ack(9F).

RETURN VALUES

None.

CONTEXT

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

NOTES

Callers must not hold any locks across a miocack() that can be
acquired as part of put(9E) processing.