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What is the difference between these two usages of system?
$cmd = "/my/code.pl";
$status = system("$cmd $var1");
vs
$cmd = "/my/code.pl";
$status = system("$cmd", "$var1");
The first (one string) invocation of
systemruns the system shell to run the command, and (amongst other things) means that the arguments to the command (from$var1) will undergo shell expansion.The second version with plural arguments bypasses the system shell and the arguments undergo no further shell processing. It is generally the recommended way of doing things. Note, however, that it means you have to worry about I/O redirection. If that’s an issue, then the first form (used carefully) is simpler. Alternatively, explore CPAN to find modules to assist – there are bound to be some.