Ok, the other monks handled this pretty comprehensively, but you need to be careful about interactive console mode apps and some (very few, but I've seen it on ancient 16 bit crap) windows apps - system() won't return until they exit. If you do this:

system("isql /Speterj /Usa /Pas_if");
system("isql /Speterj_build /Usa /Pas_if");
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You'll get one instance of isql.exe instead of 2. The second instance won't start up until the first one exits. What you need to do is this:

system("start isql /Speterj /Usa /Pas_if");
system("start isql /Speterj_build /Usa /Pas_if");
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For most Win32 Gui apps, system() returns as soon as the program is launched. --Shoeboy
perl -e "do {kill $java, $ada, $cobol, $pascal, $csh;} until die 'Just another perl hacker';"