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Unclear pointer and array

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# 29  
Old 01-20-2014
You must be on a 64-bit system. The way those have mostly worked out is that 'int' remains 32-bit, 'long int' becomes 64-bit, and pointers become 64-bit. On a 32-bit system, int, long int, and pointers are all 32-bit.

Subtracting two pointers from each other gives you a 64-bit integer, but %d expects a 32-bit integer. I think that would end up printing 0 for all numbers less than the 32-bit limit.

I would always use %ld to print pointer differences, just to be safe, since it'll work properly on both 32 and 64 bit systems.
Last edited by Corona688; 01-20-2014 at 02:50 PM..
This User Gave Thanks to Corona688 For This Post:
yifangt
# 30  
Old 01-20-2014
Great! that's what I suspected and now confirmed. Thanks a lot. Have a nice day!
Last edited by yifangt; 01-20-2014 at 08:23 PM..
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