Adding DADSM pre and post processing exit routines

All existing operator commands and system services that apply to managing dynamic exits will apply to these two dynamic exits. For example, to add an exit routine to a dynamic exit the following services could be used:

A program can use CSVDYNEX REQUEST(ADD).
The SETPROG EXIT operator command.
The EXIT statement of a PROGxx PARMLIB member, followed by the SET PROG=xx operator command.

For example using the SETPROG operator command, the following will add the IGGPRE01 exit routine to the pre-processing dynamic exit of IGGPRE00_EXIT

SETPROG EXIT,ADD,EXITNAME=IGGPRE00_EXIT,MODNAME=IGGPRE01

You can now have multiple exit routines associated with each dynamic exit.

Replacing an already active IGGPRE00 or IGGPOST0 dynamic exit routine without an IPL is also supported. For example, the SETPROG EXIT,DELETE operator command can be issued followed by the SETPROG EXIT, ADD operator command to replace a dynamic exit routine.