ML-01 Main Loop Routine

ML-01 is the main loop routine, which performs the following tasks:

  1. Initializes the message area and port file input flag at the start of every loop.

  2. Performs a complex wait.

  3. Tests the result of the complex wait, as follows: If the result is a timeout, it Restarts the main loop.

    If the result is notification of input present in the port file, it:

    • Reads the port file into the message area.

    • Sets the port file input flag.

    • Performs the paragraph SEND-TO-LINC, which passes the message on to the application. This assumes that the message data is already formatted correctly. Refer to SEND-TO-LINC for more information.

    If the result is notification of a change of port file status, it performs the paragraph PORT-CHANGE, which handles situations where the port file has been closed or its status has otherwise changed. Refer to PORT-CHANGE for more information.

    If the result is notification of a message through COMS, it performs the paragraph GET-COMS-Message, which reads the message, identifies its type, and initiates the appropriate processing. Refer to GET-COMS-Message for more information.

    If the result is invalid, it displays the invalid result.

  4. Checks to see if the COMS has instructed the NOF program to close down.