A program name is considered implicit if you specify only the basename of the program's filename in the call. For example:
CALL "myprog" USING ...
refers to a file in the following formats:
In the case of myprog.lbr, the run-time system searches the .lbr file for an executable file with the same program-name as the .lbr file, for example myprog.gnt.
Additionally, you can specify the exact location of the program to be called, by qualifying the program call with a PC drive-letter or pathname. For example, to look in the directory c:\programs for the program myprog, use the statement:
CALL "c:\programs\myprog" USING ....
Note, however, that specifying the drive or pathname is not recommended, as unexpected results can occur where the referenced module exists in more than one file, or type of format, or if the application is ported to other environments.