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

Language Elements
NCL Summary
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displays that overlay an entire screen window. They are used to present information
to users and to gather information from users.
Panel display is controlled from NCL processes. PANEL and PANELEND are the two
verbs used to control panel display. PANEL displays a panel and PANELEND
explicitly removes a panel from display. An NCL process can display many panels,
one after another, according to the input received from a user or another NCL process.
PSEND Verbs
An NCL process can act as a PATHSEND requester to communicate with existing
Pathway server classes. PSEND verbs are available for making an existing Pathway
server class available and unavailable for use by an NCL process, setting current
Pathway server class characteristics, and sending a request message to and receiving a
reply message from a Pathway server class.
START Verb
In addition to the START command, an NCL process can use the START verb to
invoke an NCL process for asynchronous execution. The START verb is more flexible
than the START command.
The START command invokes an NCL procedure for execution in the current
execution environment. The START verb allows the invoking NCL process to execute
the started NCL process in a specific environment, to synchronize execution with the
started NCL process, and to send one or more variables, including an MDO variable,
to the started NCL process. The START verb is particularly well-suited for use in NCL
processes that control the automation of operations tasks.
The START verb can also start a persistent NCL process. These NCL processes are
restarted if the Guardian process in which the NCL process is running fails. For a
restart to occur, persistent NCL processes must be executed in a background
environment.
CNM*, EMS*, INT*, LOG*, and MSG* Verbs
NCL processes can process the many messages that flow to, from, and within a
NonStop NET/MASTER MS system. There are five groups of verbs that control
message flow. The groups begin with the letters CNM, EMS, INT, LOG, and MSG:
collectively, these verbs are called message verbs.
Note The first three letters of these message verbs are called their prefix. When the prefix is important, these
verbs are referred to as CNM*, EMS*, INT*, LOG*, and MSG* verbs. The letters that follow the prefix
designate a certain function, such as deleting or reading a message. When the function is important,
these verbs are referred to by the generic suffix that describes the function. An example is xxxREAD,
which refers to all message verbs that read a message.