Exchange/RJE Manual

AWAITIO Procedure
Exchange/RJE System Procedure Calls
5–8 104698 Tandem Computers Incorporated
If your program has no more than one outstanding nowait I/O operation against a
single file at one time, you can omit this parameter. In this case, the file number
returned by AWAITIO uniquely identifies the I/O operation that was completed.
time-limit
INT(32):ref:1
specifies whether the call to AWAITIO should check for completion of the I/O
operation and return immediately, or wait for completion of the I/O operation.
The possible values of time-limit are:
> 0D Waits the specified time for completion of the I/O operation. The time to
wait is specified by time-limit in hundredths of a second (.01
seconds).
If the I/O operation does not complete in the specified amount of time,
AWAITIO returns with error number 40. A time-out error completes the
I/O operation (provided you specified a particular file in filenum ), and
the outstanding I/O operation is canceled.
0D Checks for completion of the I/O operation and returns immediately.
If the I/O operation has not yet completed, AWAITIO returns with error
number 40. The outstanding I/O operation is not canceled, and you can
call AWAITIO at a later time to check for completion again.
-1D Waits indefinitely for completion of the I/O operation. There is no limit
to how long your program will wait for the I/O operation to complete.
< -1D Illegal value; AWAITIO returns error number 22.
If you omit the time limit parameter, the default value is -1, which waits
indefinitely (no time limit) for the I/O operation to complete.
Line Activity None.
Considerations You must call AWAITIO to complete a nowait I/O operation. If you are performing
wait I/O, calls to AWAITIO are not required. In this case, control does not return to
your program until each I/O operation has completed. You specify wait or nowait
I/O in the call to OPEN that establishes communication with the Exchange/RJE line
server. For information on how to specify wait or nowait I/O, see the OPEN
procedure later in this section.