Implicit procedure protection

If a program is to be activated in a procedure, the program should check whether the procedure is protected against interruptions; i.e. the program should protect the procedure implicitly against interruptions which the program could cause during the course of its execution.

It is nevertheless possible for actions such as CMD, BKPT, STXIT, etc. to be executed by the program: first, for internal purposes; and secondly if there are user requests to this effect.
The program should interrogate the procedure attribute INTERRUPT-ALLOWED by means of a CLIGET macro call before performing any of these actions. If this attribute is set to *NO, the action should be rejected.

Programs can always be interrupted by procedure commands such as HOLD-PROGRAM.