[C] #define - unexpected Results

From: Paulie (p1150gs_at_yahoonospam.co.uk)
Date: 11/28/04 

Date: Sun, 28 Nov 2004 22:03:13 -0000

Hi all.

I just came across something that I think is weird in my program and
wondered if I was misunderstanding it or the compiler was at fault. Cut
down to the basics the program goes like this:

void foo(unsigned char);
#define NINE 9

int main (void)
{
printf("%x", NINE); // Prints out 9
foo(NINE);
blah blah
}

void foo(unsigned char a)
{
printf("%x", a);
}

I would expect the program to print out 9 as the hex value, but it actually
prints out F9 (I am working on a mainframe system using EBCDIC notation so
F9 is character '9'). Am I missing the point or is there something curious
going on that needs further investigation.

I tried it out on my PC compiler and got 9 both times (as I expected).

Thanks, Paulie

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