You are already passing a reference. Don't copy it and don't return anything (as your sub is called in void context anyway) and assign the args from @_ instead of shift:

use strict;
use warnings;

my $captains = "kirkpicard";
my %starship = (
    'EntTOS'=>0, 'EntA'=>0, 'EntD'=>0, 'EntE'=>0,
    );

trivia ($captains,\%starship);

print "Kirk was on Enterprise #:   $starship{EntTOS}, $starship{EntA}\
+n";
print "Picard was on Enterprise #: $starship{EntD}, $starship{EntE}\n"
+;

sub trivia {
     my ($captains, $starship_ref) = @_;

     if ($captains =~ m/(kirk)/) {

         $starship_ref->{'EntTOS'} = 1;
         $starship_ref->{'EntA'} = 2;

     }

     if ($captains =~ m/(picard)/) {

          $starship_ref->{'EntD'} = 4;
          $starship_ref->{'EntE'} = 5;
     }
}

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In reply to Re: Replacing original hash with modified hash returned from subroutine by hippo
in thread Replacing original hash with modified hash returned from subroutine by CommaSplice

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