Try this: 
#!perl -w

use strict;

undef $/;

my ($header, $type, $arguments);

my $file = <DATA>;

$file =~
s/((\w+)\s+(\w+)\s*\(([^)]*)\)\s*\{)/"\/* Function: $3()\n" .
                                     "      Input:\n" . do { $header =
+ $1; $type = $2; $arguments = $4 . ','; ''} .
                                     (join "\n", map { sprintf "      
+  %-5s %8s : ",
                                                       split }
                                                $arguments =~
                                                m|\s*(\w+\**\s+\**\w+)
+\s*,|g) . "\n\n" .
                                     "      Output:\n" .
                                     (sprintf "        %-5s : \n", $ty
+pe) .
                                     "\n     Author :\n     Date :\n*\
+/" .
                                     "\n\n$header"/ge;

print $file;

__DATA__
int 
function(int a, char *b) {
 ... 
 return 0;
}

[download]

I am just a little afraid that it will also catch if-blocks and such.
Hope this helped.

In reply to Re: regex 2 match C function by CombatSquirrel
in thread regex 2 match C function by jai

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