SVR5 and SCO OpenServer 5
place a message at the head of a queue
int putbq(queue_t *q, mblk_t *bp);
putbq puts a message back at the head of a queue.
If messages of a higher priority are on the queue, then
bp is placed at the head of its corresponding priority
for more information about message
All flow control parameters are updated.
The queue's service routine is scheduled
if it has not been disabled by a previous call to
Pointer to the queue.
Pointer to the message.
putbq returns 1 on success and 0 on failure.
putbq is usually called when
or, for DDI multithreaded drivers,
determines that the message cannot be passed on to the next stream component.
putbq can fail if there is not enough memory
to allocate the accounting data structures used with messages
whose priority bands are greater than zero.
High priority messages should never be put back on a queue
from within a service routine.
Base or Interrupt.
Does not block.
Driver-defined basic locks, read/write locks, and sleep locks
may be held across calls to this function.
The caller cannot have the stream frozen
when calling this function.
for an example of putbq.
1, 2, 3, 4, 5, 5mp, 6, 6mp, 7, 7mp, 7.1, 7.1mp, 8, 8mp
1, 2, 2mp, 3, 3mp, 4, 4mp, 5, 5mp, 6, 6mp
19 June 2005
© 2005 The SCO Group, Inc. All rights reserved.
OpenServer 6 and UnixWare (SVR5) HDK - June 2005