NET/MASTER Network Control Language (NCL) Programmer's Guide

Development Considerations for System-Level NCL Procedures
Developing System-Level NCL Procedures
106160 Tandem Computers Incorporated 17–13
Figure 17-1. A Closed Loop
Read Message
When Available
Begin Procedure
Wait for
Next Message
Process Message
Closed Loop
043
As each message arrives, the NCL process should process the message. Processing
involves analyzing the contents of the message and then either deleting the message
(using the EMSDEL, LOGDEL, or MSGDEL verb) or passing the message on (using the
EMSCONT, LOGCONT, or MSGCONT verb).
After processing the message, the NCL process should return to the initial EMSREAD,
LOGREAD, or MSGREAD verb, at which point the NCL process suspends processing
once again and waits for the next message.
The DO loop in the following EMSPROC NCL procedure ensures that it executes
indefinitely:
zex1704n: PROCEDURE
SAY EMSPROC starting
DO FOREVER
EMSREAD
EMSCONT
END
END zex1704n