Hi monks, this is my code 
Getopt::Long::GetOptions
        (
        'u=s' => \$user,
        'p=s' => \$passwd,
        's=s' => sub { local *_ = \$_[1];
        /^([^:]+):(\d+)$/ or die("Invalid format for option s.\n");
        $host = $1;
        $port = $2;},
        )
        or error_detect("3 Invalid commmand line options.");

[download]
now this code handles the switches u, p and s. but suppose i am supposed to give a command line swtich like h which does nothing but to invoke a help message. how do that with it.
what i mean is that all switches require some sort of argument. but if the user types in the switch -h than no argument is required with it and the program should directly print a help message.
so how does GetOpt::Long handle switches which do not require any arguments with them and their mere presence means a specific action is to be done. other examples of such switches can be -all etc etc.

In reply to handling switches with no argument using GetOpt::Long by bahadur

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