putbq - STREAMS: Places a message at the head of a queue
MBLKP message_block_ptr );
Specifies a pointer to the queue. The typedef queue_t is
an alternate name for struct queue_entry *. Specifies a
pointer to the message block. The typedef MBLKP is an
alternate name for typedef struct msgb *.
The putbq interface places a message at the beginning of
the appropriate section of the message queue. There are
always sections for high priority and ordinary messages.
If other priority bands are used, each will have its own
section of the queue, in priority band order, after high
priority messages and before ordinary messages. You can
use putbq only for ordinary and priority band messages.
High priority messages are not subject to flow-control and
thus cannot be put back on the queue.
Typically, you call putbq when the bcanput or canput
interface determines that the message cannot be passed on
to the next stream component. The flow-control parameters
are updated to reflect the change in the queue's status.
If the QNOENB flag bit is not set, putbq enables the service
Upon successful completion, putbq returns the value 1. On
failure, it returns the value zero (0).
Kernel Interfaces: bcanput(9r), canput(9r), getq(9r),
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