GDSX Manual

LINE^HANDLER Example, Running and Managing
Extended General Device Support (GDSX) Manual–134303
6-4
Running an Application Process
The wild-card character (*) directs the STATUS command to give information about all
SU objects under the LINE object.
Running an Application Process
The application terminal is used for input to and output from the example application.
Log on at the application terminal, assumed to have device name $TC1. Pause the
TACL process with the PAUSE command. Pausing the TACL process allows the
application process to control the terminal.
At the TACL terminal, start a requester application, named $A1 in this example:
> RUN APPL /NAME $A1, OUT $GDS.#LX.T1, NOWAIT/
This process must be run after the GDSX process has been started so that I/O from this
process can pass through GDSX. $A1 opens the specified OUT file. GDSE examines
the open message and determines that T1 is configured under the line
$LX, opens subdevice T1, creates a DEVICE^HANDLER task to manage
communication to T1, and notifies the LINE^HANDLER task that the SU is open.
Messages sent to T1 are routed to the DEVICE^HANDLER task, and then passed to the
LINE^HANDLER task, which sends the messages on to device $TC1, specified by the
access name for the LINE object.
The application terminal should now show a prompt sent by the application program
through the GDSE process. The prompt contains the CPU number and PIN of the
application program. From the TACL prompt you may enter:
> STATUS *, TERM
to verify this.
At the SCF terminal, enter:
-> STATUS PROCESS $GDS
The STATUS command tells you that now there are two TSCODE system tasks, and two
USCODE user tasks, a DEVICE^HANDLER task and a LINE task.
Enter:
-> STATUS, SUB ALL
The state of both T1 and LINE object is STARTED, meaning that DEVICE^HANDLER
and LINE^HANDLER tasks exist. Both T1 and the LINE object have 1 open.
The GDSX process, named $GDS, did its initialization processing and issued a
READUPDATE on $RECEIVE. Then the application program, named $A1, did its
initialization processing and issued a call to OPEN $GDS.#LX.T1. After TSCODE
received the OPEN, the SU T1 was opened, a DEVICE^HANDLER task was created to
manage communication to T1, and the LINE^HANDLER task was notified that the SU
was opened.
$GDS called REPLY with a completion code, indicating that the application’s OPEN for
$GDS.#LX.T1 was successful. After checking the condition code, the application
program issued a WRITEREAD to $GDS.#LX.T1, writing the prompt containing its