You can use a special form of the wait statement to make the process wait for interrupts. While the process is waiting for interrupts, any interrupt can execute; as soon as the interrupt completes, the process returns to its waiting state. The only way the process can continue further is if an interrupt executes a bad GO TO statement that transfers control to a different statement outside the interrupt.

Waiting for interrupts can be useful for processes, such as message control systems (MCSs), that are driven by input received over time from a variety of sources. However, waiting on multiple events might be more efficient in these cases; refer to Efficiency Considerations later in this section.

In ALGOL, the following wait statement causes the process to wait for interrupts:

WAIT;

The COBOL equivalent is the following statement:

WAIT UNTIL INTERRUPT.