On Windows, it will look for the contents of $ENV{PERL5SHELL} for a complete string (command name and switches) that it prepends to the string you are running.

If that environment variable does not exist, it uses either "CMD.EXE /X/C" or "COMMAND.COM /C" depending one whether it's running NT or Win9x.

Having different shells on Win9x vs NT can expose differences, since CMD with the /X switch does more than COMMAND.COM.

I know Perl used to use $ENV{COMSPEC} because I relied on the capabilites of my shell (the one that invoked the perl script in the first place) and found it broke at some point. That's when I learned about PERL5SHELL. I seem to recall that there was also some "common" min-shell shipped with activestate Perl at some point, to prevent differences between 9x and NT.

—John

In reply to $ENV{PERL5SHELL} by John M. Dlugosz
in thread Security concern with sudo and system() by evlg

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