Check IBM Library. Provides a means in a CL program of determining whether a
library name is considered an *IBM or *USER library and whether the library
will be saved by a SAVLIB option (e.g. SAVLIB LIB(*ALLUSR)). The command
provides a program method of providing the information from the SAVLIB chart in
the Backup and Recovery Guide. Useful for automating backup and following the
rules of the system function.