To run programs under VMS, their names are defined as DCL symbols so that typing the name runs the program. The symbol definitions are executed by running a command procedure.
Similarly, to run programs under ICL, their names are defined as ICL commands using the DEFINE command described in Chapter . Usually, the command definitions are executed by running an ICL procedure which contains them. Before a program can be run under ICL, a command to run it must be defined.
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