Why RHDCUCFB always returns a code 0 ? It does not check anything .
When issuing a job to vary the segment /file to deallocate, the files are in use and could not be deallocated but the program ended with return code zero.
RHDCUCFB is a batch interface to issue commands normally executed online. Its purpose is only to "issue the command".
It is emulating a terminal in batch. It reads the input from SYSIPT and passes each command to IDMS to execute. Any output from the command is sent to SYSLST. There is no return code set by IDMS and as far as RHDCUCFB is concerned the command execution was successful so it returns a condition code of 0. One option would be to send the SYSLST output to a dataset and write a program to read the SYSLST and determine if the DCMTs worked
The only way to determine the outcome is to interrogate the output manually (visually or write a program to do it).