There are two C functions called 'add'. One takes 2 arguments and the other takes 3 arguments

I would combine them into one function called add. Here's an Inline::C demo: 
use warnings;
use Inline C => Config =>
    BUILD_NOISY => 1;

use Inline C => <<'EOC';

int add(SV * a, ...) {
 dXSARGS;
 int i, ret = 0;

 for(i = 0; i < items; i++)
   ret += SvIV(ST(i));

 return ret;
}

EOC

print add(11, 12), "\n"; # prints 23
print add(10, 11, 12), "\n"; # prints 33

[download]
In a nutshell, the ellipsis ('...') allows you to provide any number of arguments.
The 'items' variable (enabled by calling dXSARGS) tells you how many arguments the function received - and you design the function to do whatever it's supposed to do for that number of arguments.

Cheers,
Rob

In reply to Re: Can't create XSUBs for C functions with a same name by syphilis
in thread Can't create XSUBs for C functions with a same name by Anonymous Monk

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