NAME    [Toc]    [Back]

       putbq - STREAMS: Places a message at the head of a queue

SYNOPSIS    [Toc]    [Back]

       #include <sys/stream.h>

       int putbq(
               queue_t *queue_pointer,
               MBLKP message_block_ptr );

ARGUMENTS    [Toc]    [Back]

       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 *.

DESCRIPTION    [Toc]    [Back]

       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
 interface.

RETURN VALUES    [Toc]    [Back]

       Upon  successful completion, putbq returns the value 1. On
       failure, it returns the value zero (0).

SEE ALSO    [Toc]    [Back]

       Kernel  Interfaces:  bcanput(9r),  canput(9r),   getq(9r),
       putq(9r)



                                                        putbq(9r)