SVR5 and SCO OpenServer 5

OTHERQ(D3str)

OTHERQ -- get a pointer to queue's partner queue

Synopsis

   #include <sys/stream.h>
   #include <sys/ddi.h>
   
   queue_t *OTHERQ(queue_t *q);

Description

The OTHERQ function returns a pointer to the other of the two queue structures that make up an instance of a STREAMS module or driver.

Arguments

q: Pointer to the queue.

Return values

OTHERQ returns a pointer to a queue's partner.

Usage

Context

Base or Interrupt.

Synchronization constraints

Does not block.

Multithreaded drivers may hold driver-defined basic locks, read/write locks, and sleep locks across calls to this function.

Hardware applicability

All

Version applicability

ddi: 1, 2, 3, 4, 5, 5mp, 6, 6mp, 7, 7mp, 7.1, 7.1mp, 8, 8mp
oddi: 1, 2, 2mp, 3, 3mp, 4, 4mp, 5, 5mp, 6, 6mp

References

RD(D3str), WR(D3str)

Examples

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(queue_t *q, long min, long max, ulong_t hi, ulong_t lo)
    3  {
    4	pl_t pl;	/* for multi-threaded drivers */
    5	pl = freezestr(q); /* for multi-threaded drivers */
    6	(void) strqset(q, QMINPSZ, 0, min);
    7	(void) strqset(q, QMAXPSZ, 0, max);
    8	(void) strqset(q, QHIWAT, 0, hi);
    9	(void) strqset(q, QLOWAT, 0, lo);
   10	(void) strqset(OTHERQ(q), QMINPSZ, 0, min);
   11	(void) strqset(OTHERQ(q), QMAXPSZ, 0, max);
   12	(void) strqset(OTHERQ(q), QHIWAT, 0, hi);
   13	(void) strqset(OTHERQ(q), QLOWAT, 0, lo);
   14	unfreezestr(q,pl); /* for multi-threaded drivers */
   15  }