how to get the function declaration or definitions using regex

Question

I want to get only function prototypes like

int my_func(char, int, float)
void my_func1(void)
my_func2()

from C files using regex and pytho

Answer 1

I think this one should do the work:

r"^\s*[\w_][\w\d_]*\s*.*\s*[\w_][\w\d_]*\s*\(.*\)\s*$"

which will be expanded into:

string begin:   
        ^
any number of whitespaces (including none):
        \s*
return type:
  - start with letter or _:
        [\w_]
  - continue with any letter, digit or _:
        [\w\d_]*
any number of whitespaces:
        \s*
any number of any characters 
  (for allow pointers, arrays and so on,
  could be replaced with more detailed checking):
        .*
any number of whitespaces:
        \s*
function name:
  - start with letter or _:
        [\w_]
  - continue with any letter, digit or _:
        [\w\d_]*
any number of whitespaces:
        \s*
open arguments list:
        \(
arguments (allow none):
        .*
close arguments list:
        \)
any number of whitespaces:
        \s*
string end:
        $

It's not totally correct for matching all possible combinations, but should work in more cases. If you want it to be more accurate, just let me know.

EDIT: Disclaimer - I'm quite new to both Python and Regex, so please be indulgent ;)