Application termination
The OPTIONS TERMINATE SIGNAL
defines a
callback function in case of SIGTERM signal.
Syntax
OPTIONS ON TERMINATE SIGNAL CALL function
- function is the name of a function with no parameters or return value.
Usage
The OPTIONS ON TERMINATE SIGNAL CALL function
defines
the function that must be called when the application receives the SIGTERM signal.
With this option, you can control program termination. If this statement is not called, the program is stopped with an exit value of SIGTERM (15).
When the SIGTERM signal occurs and OPTIONS ON TERMINATE CALL
is used, the
callback function is executed, and the program continues. To stop the program, perform an
EXIT PROGRAM
in the callback function, or set the int_flag and test this flag in
the processing code, to stop properly.
Use the OPTIONS ON TERMINATE SIGNAL CALL function
instruction with
care, and do not execute complex code in the callback function. The code is expected to contain only simple and short cleanup operations; any interactive
instruction is avoided.
Example
MAIN
OPTIONS ON TERMINATE SIGNAL CALL end_app
MENU "test"
COMMAND "quit" EXIT MENU
END MENU
END MAIN
FUNCTION end_app()
DISPLAY "Program terminated by SIGTERM signal..."
EXIT PROGRAM 1
END FUNCTION