Hey everybody, I'm having difficulty using the read command to perform a checksum operation. Whenever I print the final checksum, the result always returns FFFFFFFF, and I know thats not the checksum. 
Code:
 #!/usr/bin/perl -w
  
  use strict;
  use FileHandle;
  use warnings;
  my $data = "file.bin";
  my $buffer;
  my $string;
  my $n = 0;
  my $checksum = 0;
  my $num = 0;
  my $str = unpack("B32", pack("N", shift));
  my $bits = 4;
  my $decimal;

open FILE, $data or die $!;
binmode FILE;  
 while (($n = read FILE, $buffer, 4))
 {
 
 $decimal = unpack("N", pack("B32", $buffer));
 
 {$checksum = $checksum + $decimal;
 #$num = $num + $bits;}
 
 #print "1. $num\n";
 print "2. $decimal\n";
 #print "3. $n bytes read\n";
 print "4. $checksum \n";
 }
 
 $checksum = $checksum & 0xFFFFFFFF;

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Basically, I'm trying to read a binary file 32 bits at a time by unpacking them into decimal and then adding them. Furthermore, I am trying to use the $checksum & 0xFFFFFFFFF command to restrain the checksum to 32 bits. Also, just ignore the commented out stuff, I was using it for my own testing. Any assistance would be greatly appreciated.

In reply to Difficulty restraining read function to 32 bits by TeamViterbi

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