Greetings and salutions;

I am using a subroutine I found to obtain the dimansions of a gif image. The sub returns a reference to the data but when I attempt to dereference it ie. $$height or $$width I get SCALAR(0xed880) SCALAR(0xed898) instead of the values I'm looking for. I have tried returning the vars $height and $width directly but the data they contain is innacurate when compared to the original image.

Does the expression: return \($width, $height);
require some other syntax to dereference properly?

Should the syntax be: return (\$width, \$height);
to dereference properly?

This is how I am attempting to use the subroutine:

# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # 
#     Display the uploaded file.                          #
# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # 
  $MyFileName = "$ClassPath/classimg/$UpLoadedImg";
  if (-e $MyFileName){
    ($width, $height) = gifdim($MyFileName);
          if ($$height > 150){
            # If the image is too tall for the display area
            # reduce the height to fit and recalculate the width
            $NewHeight = 150;
            $NewWidth = $$width - ($$height - 150);
            }
          elsif ($width > 150){
            # If the image is too wide for the display area
            # reduce the width to fit and recalcualte the height
            $NewWidth = 150;
            $NewHeight = $$height - ($$width - 150);
            }
          # The image will fit in the display area so leave it alone
          else {
            $NewHeight = $$height;
            $NewWidth = $$width;
            }
  }
# more code ...


sub gifdim ($) {
# # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
#        Get the dimensions of a gif                      #
# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # 

    my $filename = $_[0];

    open(GIF, $filename) || return (undef, undef);
    my $buf = '';
    my $n = read GIF, $buf, 10;
    close GIF;

   return (undef, undef) if $n < 10;
    my ($head, $width, $height) = unpack("A6vv", $buf);
    ($head, $width, $height) = unpack("A6vv", $buf);

    return (undef, undef) unless $head =~ /^GIF8[79]a/;
   return \($width, $height);
#    return ($width, $height);
}

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I'm sure I'm missing something obvous but I'm stumped

My thanks to The Monastery
NereDoWell

In reply to dereferencing problem by NereDoWell

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