GDSX Manual

Overview of GDSX

Extended General Device Support (GDSX) Manual–134303

1-10

Direct Terminal Access

= SET TERM FILE $GDS.#T2

= ADD TERM TX-2

TERM TYPE specifies the type of terminal that the GDSX process is simulating for

Pathway/TS.

A session or thread is established when you issue the PATHCOM command:

= START TERM TX-2

Then the TCP opens the file specified in the configuration commands, $GDS.#T2 in this

example. Within the GDSX process, TSCODE receives the open message, derives the

device name $T2 from the message, and opens the device. GDSX then creates a

DEVICE^HANDLER task to modify the communication of the thread, by datastream

conversion, for example. For the life of the requester’s open, the thread exists from the

TCP requester through $GDS to $T2.

The typical transaction flow in this environment is shown in Figure 1-5.

When a Pathway/TS requester submits a request to GDSX, the request is picked up by

the DEVICE^HANDLER task associated with the requester, shown in Figure 1-6. The

task processes the request, and passes it to TSCODE, which passes it directly to the I/O

process. When the I/O completes, the message is picked up by the

DEVICE^HANDLER task and passed back to the requester.

Figure 1-5. Direct Terminal Access Transaction Flow

Figure 1-6. GDSX Without a LINE^HANDLER

TCP $GDS

Open

$GDS.#T2

Open

$T2

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D^H Task

TERM^FILE^NUM

TERM^FILE^NUMPseudo-

$RECEIVE File

Pseudo-

$RECEIVE File

$RECEIVE

Requester

TSCODE

$GDS

CDT021