Can somebody explain to me how to do 32-bit operations in Perl? I thought I knew this, but apparently perl works differently than what I think would be logical! I just want to add some big 32-bit numbers, which will overflow, of course. But I don't care about the 33rd bit and anything above that. I don't need them. I just want to get the first 32 bits. But everytime I try this, I either get weird results or -1 which is unexplainable!!

The result of both of these calculations below should be : 0x0000000133000000 which equals 5,150,605,312. Now, since I'm using a 32-bit software, the result ought to be 0x33000000 which equals 855,638,016. But I get neither of those!!! Why?

printf("\nLINE 1: 855638016 == %d", 0x34000000 + 0xFF000000);

print "\nLINE 2: 855638016 == ", (872415232 + 4278190080) & 0xFFFFFFFF;

This is what TinyPerl 5.8 on WinXP prints on my computer screen:

LINE 1: 855638016 == -1
LINE 2: 855638016 == 4294967295

(Notice that both of these numbers are the same thing. -1 = 0xFFFFFFFF = 4294967295. But on the first line, I get -1, and on the second line I get the positive number in base 10. This is totally unacceptable! What is going on here???

In reply to perl arithmetic is killing me! HELP! by harangzsolt33

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