Try to change your code this way: 
my $sys = $^O;
my $lim;
if ($sys eq "linux") { 
     $lim="clear";
} else {
     $lim="cls";
}
# ...

[download]
You actually don't really need the $sys variable, you could compare dirfectly $^O, but it does not matter.

In reply to Re: Global symbol requires explicit package.. by Laurent_R
in thread Global symbol requires explicit package.. by meanroc

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