test.pl
--------------------
use hello qw(addint);

my $a=addint(9, 16);
print "$a\n";
exit;


hello.pm
------------
package hello;
use strict;
require Exporter;
@ISA=qw(Exporter);
@EXPORT_OK=qw(addint);

use Inline (C => 'cfunction/addint.c');
1;


addint.c
-----------------------------
int addint(int x, int y) {
  return x + y;
}