Using a perl type case statment (sometimes called a hash) can work well for this type of problem. 
sub help {
   print(@_);
   print(" This is help?\n");
}

sub list {
   print("This is list\n");
}

our $commands = {
    'help' => \&help,
    'list' => \&list,
};

while (<STDIN>) {
    chomp;
    if ((my $name) = ($_ =~ /^(\w+)/)) {
        if (defined $commands->{$name}) {
            $commands->{$name}->($_);
        } else {
            print "I Don't understand $name\n";
        }
    }

}

[download]
-- gam3
A picture is worth a thousand words, but takes 200K.

In reply to Re: problem with input command by gam3
in thread problem with input command by white-fox

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