error_get_last() and custom error handler

Question

odbc_errormsg does not report error messages from odbc_execute the way it\'s supposed to. It merely throws a warning. So I\'ve been forced to write a hack to parse the erro

Answer 1

You could change your custom error handler to return false, just when the error is ignored (@-operator used).

function custom_error_handler($errno, $errstr, $errfile, $errline){
    $ignore = ($errno & error_reporting()) == 0;
    if ($ignore) {
        return FALSE;
    }
    echo "[Error happened: $errstr]\n";
    return TRUE;
}

Answer 2

Right, this is a bizarre solution, but I think it will suit your purposes.

After a bit of playing around, I have discovered that this:

function my_error_handler ($errno, $errstr, $errfile = '', $errline = 0, $errcontext = array()) {

  // Handle the error here

  @trigger_error($errstr);
  return TRUE;

}

// Just to make sure PHP is not outputting anything
error_reporting(-1);
ini_set('display_errors',1);

set_error_handler('my_error_handler');

// An E_USR error...
trigger_error('Some error');
var_dump(error_get_last());

// ...and a native one
$key = count();
var_dump(error_get_last());

Results in this:

array(4) {
  ["type"]=>
  int(1024)
  ["message"]=>
  string(10) "Some error"
  ["file"]=>
  string(69) "C:\Program Files\Apache Software Foundation\Apache2.2\htdocs\test.php"
  ["line"]=>
  int(7)
}
array(4) {
  ["type"]=>
  int(1024)
  ["message"]=>
  string(45) "count() expects at least 1 parameter, 0 given"
  ["file"]=>
  string(69) "C:\Program Files\Apache Software Foundation\Apache2.2\htdocs\test.php"
  ["line"]=>
  int(7)
}

Calling @trigger_error() from within your error handler, and not returning FALSE, causes error_get_last() to return something other than NULL, but because the error is suppressed with @, PHP doesn't output anything. It seems that in the interests of avoiding an infinite recursion, calling trigger_error() from within the registered error handler function does not call the error handler - which works to our advantage here.

Obviously, the error code has been modified, but you could convert it to the relevant E_USR_* code if you need - but I suspect what you really want is the string value, which this method will allow you get. You have, unfortunately, also lost the line number and file information - although you could possibly get this back by doing something involving a stack trace inside the error handler, or at the very least including it in the string from the arguments passed.

This is a horrible, horrible, horrible hack - but since there is no officially sanctioned way to do this, a hack is essentially what you are asking for.