function - get_magic_quotes_gpc() and mysql_real_escape_string - security -

i practicing php , puzzled while interpreting function escape dangerous sql characters. want know how works $value in second if. quiet puzzling me understand actual flow of function.

function quote_smart($value, $handle) {     if (get_magic_quotes_gpc()) {        $value = stripslashes($value);    }     if (!is_numeric($value)) {        $value = "'" . mysql_real_escape_string($value, $handle) . "'";    }    return $value; } 

what code basically;

• first removes effect of magic_quotes_gpc if , if it's enabled in server. should not since magic_quotes has been deprecated while (and removed entirely in new php versions).

• second, encloses non numeric values of $value in single quotes, , escapes value using mysql_real_escape_string avoid sql injection in value string.

using recent versions of php, method should not exist @ all, since magic_quotes_gpc should never enabled, , you'd using pdo or mysqli parameterized queries not need values escaped.