Function escaping quote is not working correctly

I'm trying to figure out why this function does not work correctly.

It's adding an extra \ every time I edit my entries.

Online server has these settings:

magic_quotes_gpc On 
magic_quotes_runtime Off 
magic_quotes_sybase Off

Here is the code:

function esc($s)
{
  if (get_magic_quotes_gpc()) {
    if (ini_get('magic_quotes_sybase'))
      $s = str_replace("''", "'", $s);
    else
      $s = stripslashes($s);
  } //if 
  return mysql_real_escape_string($s);
}

Edit note:

I have tried completely removing this function to see what it does... and it does the same thing, so I have realized that addslashes is also use in the code for the same thing.

The extra \ were there because magic_quote was ON

Ok I have fixed the problem. A quick solution for now, I have removed function esc($s).
I changed Magic_Quote to OFF in php.ini.
I'm keeping addslashes solution.