$err .= "missing cmd or data," unless $cmd && $data;
$err .= "invalid command ($cmd)," unless $cmd =~ /^[A-Z][A-Z0-9]*$/;
my ($gp, $tus) = split /:/, $group, 2 if $group;
$err .= "missing cmd or data," unless $cmd && $data;
$err .= "invalid command ($cmd)," unless $cmd =~ /^[A-Z][A-Z0-9]*$/;
my ($gp, $tus) = split /:/, $group, 2 if $group;