As part of a test suite, I need to test that two programs cannot run at the same time. 
$rc = system("perl $rpla & perl $rplb & ");
ok($rc,  'double rpl dies with rc=' . $rc);

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When run from a shell as perl prog-rpla.pl & perl prog-rplb.pl & rpblb dies as it starts before rpla finishes.

However, when run as via system, the test above fails -- that is, rc=0, which means system did NOT fail as desired.

My question: what does  system("foo & bar&") return? Which return value?

Thanks

water

And yes, this is a test suite, so I'm not concerned about taint and the one-arg form of system...

In reply to multi-command sytem call by water

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