select_enqueue(9r) [osf1 man page]

select_enqueue(9r)														select_enqueue(9r)

NAME

       select_enqueue - General: Adds the current kernel thread

SYNOPSIS

       void select_enqueue(
	       sel_queue_t *selq );

ARGUMENTS

       Specifies a pointer to a sel_queue structure.

DESCRIPTION

       The select_enqueue routine adds the current kernel thread to the list of kernel threads waiting for a select event on the specified device.
       This routine is called when a kernel module's select routine has been called and the requested event cannot be immediately satisfied.   For
       example,  the  requested  event	cannot	be immediately satisfied when xxselect is called for the following reasons: To select on input and
       there are no characters available When called for output and the kernel module's output buffers are currently full

       By calling select_enqueue, the kernel module's select routine ensures that the kernel thread issuing the select call will be blocked  until
       the requested event can be satisfied or until the select call terminates.

CAUTIONS

       You must call the queue_init routine to initialize the sel_queue structure pointer prior to calling select_enqueue. Failure to do so causes
       the kernel to panic.

RETURN VALUES

       None

FILES

SEE ALSO

       Routines: queue_init(9r), select_dequeue(9r), select_dequeue_all(9r), select_wakeup(9r)

       Data Structures: sel_queue(9s)

       System Calls: select(2)

																select_enqueue(9r)

select_wakeup(9r)														 select_wakeup(9r)

NAME

       select_wakeup - General: Wakes up a kernel thread

SYNOPSIS

       void select_wakeup(
	       sel_queue_t *selq );

ARGUMENTS

       Specifies a pointer to a sel_queue structure.

DESCRIPTION

       The  select_wakeup  routine  wakes  up  a  kernel thread that is suspended while waiting for an event on the specified device. A user-level
       process can use the select system call to cause the process to be suspended while waiting for an event to happen on a device. For  example,
       a  graphics  application  may issue a select call while waiting for mouse or keyboard input to arrive. In this case the process would issue
       the select system call, which would indirectly call the graphics driver's select routine (through the driver's select entry  point  in  the
       dsent  table)  to  determine if any input is available. If input is available, the select call may return immediately.  If no input is cur-
       rently available, the graphics driver would suspend the process until input arrived.

       For this example, when the graphics driver has received input (typically through its interrupt handler), it causes any processes  suspended
       from  calling  select  to continue by calling the select_wakeup routine.  This causes any process currently suspended on the select channel
       (as specified by the selq argument) to resume.

RETURN VALUES

       None

SEE ALSO

       Routines: select_dequeue(9r), select_dequeue_all(9r), select_enqueue(9r)

       System Calls: select(2)

																 select_wakeup(9r)