I am using Getopts to pull some command line switches. I have one optional switch, -l, that when used requires an argument. Here's my code: 
$opts = getopts ('uhal:',\%Options);

if ($opts) {

    $print_users = $Options{u};

    $print_all = $Options{a};

    if ($Options{l}) {
        $logfile=$Options{l};
    } else {
        $logfile="$IDEAS_DIR/sec/logs/daemon.$HOSTNAME";
    }

    if ($Options{h}) {
        ShowUsage();
    }

} else {
    ShowUsage() ;    
}

[download]
so you can see that I am using the "l:" spec to Getopts to show a required argument. When the user doesn't present an argument after -l, however, I don't see how to detect that condition (apart from another condition that might cause the Getopts call to raise an error). $Options{l} doesn't seem to get set in this case, so I can't determine for myself that "yeah they did a -l, but did no argument", and Getopts itself doesn't issue any error messages about forgetting a required argument. When the user forgets the -l argument, I'd like to tell them that they forgot it, but I don't see how I can tell without going ahead and parsing @ARGV myself .. and if I do that, why even use Getopts in the first place? Any suggestions?

In reply to Getopts and required args by husker

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