Special parameters declaration function in C [duplicate]

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Possible Duplicates:

C function syntax, parameter types declared after parameter list

What is useful about this C syntax?

Why are declarations put between func() and {}?

Hi guys,

I downloaded the glibc. I want to reuse some code part from this librairy, but there is somethings weird in this 开发者_开发技巧code. In fact, the parameters declaration are strange. The type of the parameters declared after que parantheses. I never saw that before. What is this kind of declaration? I not am able to compile it.

void
_ufc_doit_r(itr, __data, res)
     ufc_long itr, *res;
     struct crypt_data * __restrict __data;
{
/*CODE HERE */
}

---

This is called "K&R" style, from Kernighan and Ritchie, who wrote the book The C Programming Language. In the first edition of that book, the above was the only way to declare the types of parameters. I believe the second edition uses the standard style, with the types and names both within parentheses:

void
_ufc_doit_r(ufc_long itr,
            struct crypt_data * __restrict __data,
            ufc_long *res)
{
/*CODE HERE */
}

K&R style is a very old style of declaring parameters, but some people still use it so their code can compile on very old compilers.

---

That's the old style of declaring the datatypes for the arguments. It's modern equivelent would be:

void
_ufc_doit_r(
     ufc_long itr,
     struct crypt_data * __restrict __data,
     ufc_long res
)
{
/*CODE HERE */
}