What does "define" in C code without a # in front of it mean? For example, what's the difference between these two lines:
define retadd "\x9f\x45\x3a\x77"
#define port 110
I found this in code found here: https://www.exploit-db.com/raw/643/
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3I'd call that a bug in the code. – dbush Nov 03 '17 at 18:32
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2It is **clearly** a typo. If you look at the use, it would work if you just `#define`d it like everything else – Antti Haapala -- Слава Україні Nov 03 '17 at 18:36
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2Or, rather, it is a security feature, so that non-c-savvy people couldn't readily use the exploit. – Antti Haapala -- Слава Україні Nov 03 '17 at 18:37
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2Could it be already 'defined' like #define define #define ? Just a thought...But i agree that its probably a typo – Grantly Nov 03 '17 at 18:40
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@Grantly: No, you can't do that. The `#` operator stringifies its arguments, and it's only usable in function-like macros. – Tim Čas Nov 03 '17 at 18:42
2 Answers
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It’s not standard C: that’s for sure.
It might be something very compiler specific or a bug in the source code.
Bathsheba
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Just to expand on what you said: I wondered, "Perhaps you could define a preprocessor macro without `#`, and this is what happened above?" but the answer to that is no: https://stackoverflow.com/a/8289287/1462295 – BurnsBA Nov 03 '17 at 18:38
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define without a leading # is just another identifier, and in that context would be a syntax error (it's not a declaration specifier or type name, which is what the compiler expects at that point). That code must be a typo.
John Bode
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