Return specifications

For the IRXTERM termination routine, the contents of the registers on return are:

Register 0: If you passed the address of an environment block, IRXTERM returns the address of the environment block for the previous environment. If you did not pass an address, register 0 contains the same value as on entry.
If IRXTERM returns with return code 100 or 104, register 0 contains the abend and reason code. Return codes describes the return codes and how IRXTERM returns the abend and reason codes for return codes 100 and 104.
Registers 1-14: Same as on entry
Register 15: Return code