Link-editing PL/I subroutines for later use

To prelink PL/I subroutines, store them in a load library, and later INCLUDE them with main procedures. The subroutines must be linked with the NCAL link-edit option which causes unresolved external reference error messages from the link-edit process, but these are resolved when the PL/I main procedure is linked with the subroutines. The NCAL option is needed because, in a PL/I load module, all the resident modules must be at the same level. This consistency is ensured because external references are not resolved until the final link.