Why c functions can be defined this way? [duplicate]

问题

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Closed 9 years ago.

Possible Duplicates:
What is useful about this C syntax?
What is this strange function definition syntax in C?

static void
add_shopt_to_alist (opt, on_or_off)
     char *opt;
     int on_or_off;
{
...
}

What's the syntax for :

(opt, on_or_off)
         char *opt;
         int on_or_off;

?

来源：https://stackoverflow.com/questions/4191649/why-c-functions-can-be-defined-this-way