printf messing up hex numbers

So, I have a hex file that I read into a vector. and now I'm printing out it's contents by doing a good ol' printf. When it does this I am surprised to see vaules that were FF in my hex editor come up as FFFFFF80, FFFFFFFF, FFFFFF98 and other things like that. I assumed that maybe the hex editor, when it displayed them, just left off the end to these numbers, so I did a printf("%.2X",hexnumber); and that gave me the same result. Why is this happening and why are the FF's in my editor being displayed as something else in the program?

Without seeing soms code it's not clear what you want to do.
Something like this ?

Code:

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#include <stdio.h>

int main() {
    int x = -128;
    printf("=%2X\n", x & 0xff);
}

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Kurt

instead of taking an int as argument, my guess would be to use an unsigned char.

Quote:

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Originally Posted by Richard.J

instead of taking an int as argument, my guess would be to use an unsigned char.

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Hexadecimal is just a different representation of the underlying data type - may it be an integer, character, pointer etc.

that is of course correct, but if you try to printf an integer, the result may vary depending on the value input. I. e. a negative integer or a byte value with the MSB set may be prepended by 0xFF