CMEM Support for IBM FTP

The IBM FTP process is executed under the OMVS address space, which is BPXAS. BPXAS address spaces do not usually write messages to the JESYSMSG.

In order to enable CMEM DSNEVENT support for IBM FTP, the following occurs:

1. When the CMEM monitor starts, it activates the OpenEdition interface for processes in the BPXAS. Having done this, CMEM issues the following messages:

   CTO782I SUBSYSTEM REGISTERED WITH OPENEDITION INTERFACE

   CTO783I INITIALIZATION OF OPENEDITION ENVIRONMENT ENDED SUCCESSFULLY

   When CMEM initialization is complete, message CTO147I is displayed. After this, CMEM gets control every time that an OpenEdition process starts in the BPXAS address space.

2. When a new process starts in the BPXAS, the interface routine issues the CTO403I pseudo-message. This pseudo-message causes CMEM to simulate IEF403I processing, which is described in Support for ON DSNEVENT and ON STEP.
3. Under z/OS, IBM FTP functions as a UNIX process running under z/OS. Therefore it follows the UNIX standard, one aspect of which is that the name of the job is set to the user ID of the person who issued the FTP request. This UNIX standard creates a problem, because the operator who writes the CMEM rule must know at that stage which user will issue an FTP request.

   The solution to this problem is to use the statement ON DSNEVENT FTP*. The result is that any FTP process will trigger the rule.

Note: Do not use the STEPRC subparameter in conjunction with the FTP* setting for ON DSNEVENT, because the same FTP procedure can serve many requests before being terminated.