I would probably simplify the code to this:

#!/usr/bin/perl -w
use strict;

my $msg = "Please turn off your machines";

for ( 1..10 )
{
  system ( "echo $msg | smbclient -M mach-$_" );
}
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This assumes that your machine's NETBIOS names run from mach-1 to mach-10. it seems fairly simple .. why do you think you need a CPAN module to make this simpler?