The SPAWN Command

There is also a way round the restriction mentioned above. This is to use the command SPAWN rather than the $ command. For example:

    ICL> SPAWN COPY
    _From: *.DST
    _To: DATADIR:*.DST

in which case we get the From: and To: prompts just as we do in normal DCL. The disadvantage of SPAWN is that it is normally much slower. This is because SPAWN creates a new subprocess to issue each command, whereas DCL creates a permanent subprocess in which all commands are issued.

SPAWN has another use -- by just typing SPAWN we can get a DCL $ prompt from which a series of DCL commands can be executed. LOGOUT is then used to return control to ICL.