Obfuscated Code in C

Question

Please explain how the following snippet of code in C is a valid one

int main(c, v) char *v; int c;{
 //program body
}

I stumbled across some examples from the International Obfuscated C code contest and i'm just curious.

Refer to this question: http://stackoverflow.com/questions/8869768/defining-the-functions-argument-type-after-the-is-it-a-very-old-standard — Renan Greinert, Jan 27 '12 at 13:44

score 9 · Accepted Answer · edited May 23 '17 at 12:27

9

It's K&R-style function declaration. See Function declaration: K&R vs ANSI

However, I don't believe it has a valid signature for main(), since v isn't of the right type. See What are the valid signatures for C's main() function?

edited May 23 '17 at 12:27

Community

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answered Jan 27 '12 at 13:36

NPE

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score 2 · Answer 2 · answered Jan 27 '12 at 13:35

2

It's the pre-ANSI style of function declaration, if you're referring to why the char*v; int; is outside of the parentheses.

answered Jan 27 '12 at 13:35

Roel

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score 0 · Answer 3 · answered Jan 27 '12 at 13:36

0

This is "K&R C", in which function arguments are declared between the end of the argument list and the start of the function's body.

answered Jan 27 '12 at 13:36

unwind

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score 0 · Answer 4 · answered Jan 27 '12 at 13:36

0

That's just the K&R-style function definition, that, although marked "obsolete", is still allowed by the standard. What is not fine in that code is that the first parameter should be char **v (or char *v[]) to be standard.

answered Jan 27 '12 at 13:36

Matteo Italia

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Obfuscated Code in C

4 Answers4