use strict;

my %systemcmd = (
    add       => "addqueue -h P0 -q P1 -i 3",
    remove    => "removequeue -f -q P0",
    status    => "lpstat -pP0",
    cancel    => "cancel -e P0",
    add_slurp => "addqueue -h P0 -q P1 -i 3"
);

my $file = <<FILE;
add wibble ping

cancel wobble
flibble one
FILE

open INFILE, '<', \$file;

while (<INFILE>) {
    chomp;
    next unless length;

    my ($command, @params) = split;

    unless (exists $systemcmd{$command}) {
        warn "Unrecognised command: $command in line $.\n";
        next;
    }

    my $cmdline = $systemcmd{$command};

    $cmdline =~ s/(P$_)/$params[$_]/e for 0 .. $#params;
    print qq{system ("$cmdline");\n};
}

close INFILE;

##</code><code>##

system ("addqueue -h wibble -q ping -i 3");
Unrecognised command: flibble in line 4
system ("cancel -e wobble");