Tribblix: manual page: OTHERQ.9f

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

NAME

OTHERQ, otherq - get pointer to queue's partner queue

SYNOPSIS

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

queue_t *OTHERQ(queue_t *q);

INTERFACE LEVEL

Architecture independent level 1 (DDI/DKI).

PARAMETERS

q
Pointer to the queue.

DESCRIPTION

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.

RETURN VALUES

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

CONTEXT

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

EXAMPLES

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 }