USE_EXTSM

Set this variable to indicate that the runtime should use an external sort module. When USE_EXTSM is set to 1 (on, true, yes), the runtime uses the linked-in EXTSM function to perform the SORT or MERGE operation. When USE_EXTSM is set to the default value of 0 (off, false, no), the runtime does not perform any special handling for SORT and MERGE verbs.