I don't want to make this hash 'palette' global, but rather pass it to a subroutine, have the hash updated, and then the result passed back, ideally 'palette' is now updated. This code is just my (last bad) guess at doing it.

Not a speed issue.

The problem seems to be with the hash, after it has been passed back. 

  use strict;
  use warnings;

  my $i;
  my %palette;

  $palette{'palette_info'}[0]    = 128;
  $palette{'mask_info'}[0]       = 0;
  $palette{'shade_stencil_mask'} = 99 ;
  
  my $data;

  ($data) = &writeCmd(111, \%palette, 222, 333);
  map { print "$_ => $$data{$_} \n" } keys %$data;

  # Problem starts after this point, how to update %palette

  %palette = %$data;  # just my last guesss is here now

#  printf("main : data info = %d, \n", $palette->{'palette_info'}[0]);
#  printf("main : data shade_stencil_mask = %d, \n", $palette->{'shade
+_stencil_mask'});

  printf("main : data info = %d, \n", $data->{'palette_info'}[0]);
  printf("main : data shade_stencil_mask = %d, \n", $data->{'shade_ste
+ncil_mask'});


exit(0);

#******************
sub writeCmd() {
#******************
#
#

  my $command = shift;
  my $pal     = shift;
  my $address = shift;
  my $length  = shift;

  map { print "$_ => $$pal{$_} \n" } keys %$pal;

# palette_info[0]  mask_info'}[0]   'mask_info'}[0]  'shade_stencil_ma
+sk'

  printf("WriteCommand : cmd, addr, len = %d, %d, %d\n", $command, $ad
+dress, $length);

  printf("WriteCommand : pal info = %d, \n", $pal->{'palette_info'}[0]
+);
  printf("WriteCommand : pal shade_stencil_mask = %d, \n", $pal->{'sha
+de_stencil_mask'});

  $pal->{'palette_info'}[0] = 444;
  $pal->{'shade_stencil_mask'} = 234;

  return($pal);

} # end of writeCmd()

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In reply to returning hash from sub problems by gibsonca

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