Copyright 1989 AT&T
Copyright (c) 2006, Sun Microsystems, Inc., All Rights Reserved
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#include <sys/stream.h> #include <sys/ddi.h> queue_t *OTHERQ(queue_t *q);
Architecture independent level 1 (DDI/DKI).
q
Pointer to the queue.
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