Abigail-II's suggestions is best on *nix. If you are stuck on Windows I would recommend Win32::Process

use Win32::Process;
my $ProcessObj;
while(1) {
    Win32::Process::Create(
        $ProcessObj, 
        $appname, 
        $cmdline,
        $iflags,
        $cflags,
        $curdir) or die;
    $ProcessObj->Wait(INFINITE);
}
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flounder