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

NAME

merror - Send an M_ERROR message upstream

SYNOPSIS

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


void merror(queue_t *wq, mblk_t *mp, int error);

INTERFACE LEVEL

illumos DDI specific (illumos DDI).

PARAMETERS

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


mp
Optionally, a STREAMS message to convert to an M_ERROR.


error
Error code to include in the M_ERROR message.

DESCRIPTION

The merror() function constructs an M_ERROR message, and sends the
resulting message upstream.


If mp is NULL, merror() allocates a one-byte M_ERROR message. If mp is
non-NULL, merror() attempts to convert the passed-in message to an
M_ERROR. However, if the passed-in message has more than one reference
(see dupmsg(9F)), or if it is of zero length, it is freed and a new
message is allocated.


If the allocation or conversion fails, merror() silently fails.
Otherwise, the resulting one-byte data block is assigned the specified
error code and sent upstream.

RETURN VALUES

None.

CONTEXT

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

NOTES

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

SEE ALSO

put(9E), dupmsg(9F)


STREAMS Programming Guide

June 9, 2004 MERROR(9F)