This isn't really a SAS question but a question about how to use korn shell so this may not be the best place to ask, but if you wanted to run one script from another wouldn't you just put the path to that script in your "master" script?
#!/bin/ksh
/path/to/file1.ksh
If you wanted to source the file rather than run it you could use the "source" command or it's alias, ".":
. /path/to/file1.ksh
or
source /path/to/file1.ksh
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Greg Wootton | Principal Systems Technical Support Engineer