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Copyright 1989 AT&T
Copyright (c) 2006, Sun Microsystems, Inc., All Rights Reserved
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OTHERQ, otherq - get pointer to queue's partner queue

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



queue_t *OTHERQ(queue_t *q);

Architecture independent level 1 (DDI/DKI).

q

The OTHERQ() function returns a pointer to the other of the two queue structures that make up a STREAMS module or driver. If q points to the read queue the write queue will be returned, and vice versa.

The OTHERQ() function returns a pointer to a queue's partner.

The OTHERQ() function can be called from user, interrupt, or kernel context.

Example 1 Setting Queues

This routine sets the minimum packet size, the maximum packet size, the high water mark, and the low water mark for the read and write queues of a given module or driver. It is passed either one of the queues. This could be used if a module or driver wished to update its queue parameters dynamically.

 1 void
 2 set_q_params(q, min, max, hi, lo)
 3 queue_t *q;
 4 short min;
 5 short max;
 6 ushort_t hi;
 7 ushort_t lo;
 8 {
 9 q->q_minpsz = min;
10 q->q_maxpsz = max;
11 q->q_hiwat = hi;
12 q->q_lowat = lo;
13 OTHERQ(q)->q_minpsz = min;
14 OTHERQ(q)->q_maxpsz = max;
15 OTHERQ(q)->q_hiwat = hi;
16 OTHERQ(q)->q_lowat = lo;
17 }

Writing Device Drivers

STREAMS Programming Guide