Limitations of DPL server programs

A DPL server program cannot issue the following types of commands.

  • Terminal-control commands referring to its principal facility
  • Commands that set or inquire on terminal attributes
  • BMS commands
  • Signon and signoff commands
  • Batch data interchange commands
  • Commands addressing the TCTUA
  • Syncpoint commands (except when the client program specifies the SYNCONRETURN option on the LINK request).
If the client specifies SYNCONRETURN:
  • The server program can issue syncpoint requests.
  • The mirror transaction requests a syncpoint when the server program completes processing.
Attention: Both these kinds of syncpoint commit only the work done by the server program. In applications where both the client program and the server program update recoverable resources, they could cause data-integrity problems if the client program fails after issuing the LINK request.

For further information about application programming for DPL, see Application programming for CICS DPL.