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

NAME

SAMESTR, samestr - test if next queue is in the same stream

SYNOPSIS

#include <sys/stream.h>


int SAMESTR(queue_t *q);

INTERFACE LEVEL

Architecture independent level 1 (DDI/DKI).

PARAMETERS

q
Pointer to the queue.

DESCRIPTION

The SAMESTR() function is used to see if the next queue in a stream
(if it exists) is the same type as the current queue (that is, both
are read queues or both are write queues). This function accounts for
the twisted queue connections that occur in a STREAMS pipe and should
be used in preference to direct examination of the q_next field of
queue(9S) to see if the stream continues beyond q.

RETURN VALUES

The SAMESTR() function returns 1 if the next queue is the same type
as the current queue. It returns 0 if the next queue does not exist
or if it is not the same type.

CONTEXT

The SAMESTR() function can be called from user, interrupt, context.

SEE ALSO

OTHERQ(9F)


Writing Device Drivers


STREAMS Programming Guide

January 16, 2006 SAMESTR(9F)