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• With arguments or without

• Locally or on a remote G2 or G2 Gateway process

• Optionally with a priority or after a time interval

When starting a remote procedure, because of this scheduling order, it is possible for the remote procedure to complete before the remainder of the calling rule or procedure. To invoke a procedure synchronously from a procedure, use the call statement, as described under call.

You cannot use the start action to obtain a return value from a procedure: any value returned by a started procedure is discarded. Use start with caution for operations such as writing to a file: by the time the started procedure executes, the data it was to write may no longer exist, or the stream it was to write to may no longer be open.

A started procedure cannot assume that the context that existed when it was scheduled still exists. Any amount of processing may have occurred between its scheduling and its invocation by the scheduler. Once the procedure starts, it can assume that nothing else in the KB will execute unless the procedure enters a wait state, as described under Allowing Other Processing.

Starting a Procedure

To start a procedure:

start procedure ( [argument [ , ...] )

This example shows an action button that starts a procedure, using the this window statement to pass the current g2-window as the single argument of the procedure.

Starting a Procedure on a Remote G2 Process

To start a procedure on a remote G2 or G2 Gateway process:

start procedure ( [argument [ , ...] ) across {g2-to-g2-interface | gsi-interface}

Starting a Procedure with a Priority

To start any procedure with a non-default priority:

start procedure ( [argument [ , ...] ) at priority integer-expression

Specifying a priority overrides the default priority of the invoked procedure. Here is an example of the optional priority statement:

Starting a Procedure after a Time Interval

To start any procedure after a time interval:

start procedure ( [argument [ , ...]) after time-interval

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