How to Percolate a Message

If you determine that an exception message is not recognized by your handler, you can percolate the exception message to the next available handler. For percolation to occur, the exception message must not be considered as a handled message. Other exception handlers in the same or previous call stack entries are given a chance to handle the exception message. The technique for percolating an exception message varies depending on the type of exception handler.

For a direct monitor handler, do not change the exception message to indicate that it has been handled. A normal return from your exception handler causes the system to percolate the message. The message is percolated to the next exception handler in the exception handler list for your call stack entry. If your handler is at the end of the exception handler list, the message is percolated to the first exception handler in the previous call stack entry.

For an ILE condition handler, you communicate a percolate action by setting a return code value and returning to the system. For information about the actual return code values for the Register a User-Written Condition Handler (CEEHDLR) bindable API, see the API topic collection in the Programming category of the IBM® i Information Center.

For an HLL-specific handler, it may not be possible to percolate an exception message. Whether you can percolate a message depends on whether your HLL marks the message as handled before your handler is called. If you do not declare an HLL-specific handler, your HLL can percolate the unhandled exception message. Please refer to your ILE HLL reference manual to determine the exception messages your HLL-specific handler can handle.