Another option is to use List::Compare :
Untested pseudocode .. 
use List::Compare;

my @required_patches= qw(patch numbers that are required);
my @current_machine_patches= ....;

my $lc =  List::Compare->new(
  {lists => [\@required_patches, \@current_machine_patches],
        accelerated => 1,
        unsorted => 1
  });

my @missing_patches = $lc->get_Lonly;

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     "For every complex problem, there is a simple answer ... and it is wrong." --H.L. Mencken

In reply to Re: Finding out what computer does NOT have certain data by NetWallah
in thread Finding out what computer does NOT have certain data by Sunnmann

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