Why no PHP error on call to undefined function?

Question

Whenever there is a call to an undefined function, no errors are logged. Instead the script just stops executing. To make things worse, if I run php -l filename.php, It shows that there are no syntax errors. I am using a custom error handler function, but even the first line is never reached.

How can I get it to run my error handler when there is a call to an undefined function?

I am using PHP 5.3.2-1. Here is the code that is setting the error handler:

error_reporting(-1);
$old_error_handler = set_error_handler( "userErrorHandler" );
set_exception_handler('exception_handler');

Neither the error handler nor the exception handler are being reached, although they do work for other errors.

The reason I want this is I end up having to place debug statements in my code to see how far it gets before it stops executing which is a slow process compared to an error message that would tell me the file and line number where the error is.

Petah · Accepted Answer · 2011-10-26 00:21:23Z

11

Fatal errors can not be caught by a user error handler.

See http://php.net/manual/en/function.set-error-handler.php

Specifically the part:

The following error types cannot be handled with a user defined function: E_ERROR, E_PARSE, E_CORE_ERROR, E_CORE_WARNING, E_COMPILE_ERROR, E_COMPILE_WARNING, and most of E_STRICT raised in the file where set_error_handler() is called.

And as per the comments on the PHP manual page, one work around is to test for errors in the shutdown function:

<?php
    error_reporting(E_ALL);
    ini_set('display_errors', 0);

    function shutdown(){
        $isError = false;
        if ($error = error_get_last()){
            switch($error['type']){
                case E_ERROR:
                case E_CORE_ERROR:
                case E_COMPILE_ERROR:
                case E_USER_ERROR:
                    $isError = true;
                    break;
            }
        }

        if ($isError){
            echo "Script execution halted ({$error['message']})";
        } else {
            echo "Script completed";
        }
    }

    register_shutdown_function('shutdown');
?>

answered Oct 26, 2011 at 0:21

Petah

46.2k30 gold badges161 silver badges216 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

Peter Over a year ago

+1 for completeness (both "why id doesn't work" and the workaround)

DivergentSpaceTimeWanderer Over a year ago

This workaround works great! I also added the following cases to the switch statement based on the documentation you linked to: E_PARSE, E_COMPILE_WARNING, E_STRICT. Based on the documentation it seems that catching E_STRICT errors in this way would cause duplicate logging of errors at times, but it is necessary in order to log all errors. I am basing this on the documentation saying that "most" E_STRICT errors cannot be handled with a user defined function.

DivergentSpaceTimeWanderer Over a year ago

Also the documentation does not include E_USER_ERROR in the list of error types that cannot be handled by a user defined function, so I removed that case from the code you posted.

DivergentSpaceTimeWanderer Over a year ago

As part of this workaround, I also like to call my custom error handler from inside the shutdown function for the error types that would not already be caught by it.

alex · Accepted Answer · 2011-10-26 00:21:53Z

0

There is a relevant part in the manual for set_error_handler().

The following error types cannot be handled with a user defined function: E_ERROR, E_PARSE, E_CORE_ERROR, E_CORE_WARNING, E_COMPILE_ERROR, E_COMPILE_WARNING, and most of E_STRICT raised in the file where set_error_handler() is called.

answered Oct 26, 2011 at 0:21

alex

492k205 gold badges890 silver badges992 bronze badges

Collectives™ on Stack Overflow

Why no PHP error on call to undefined function?

2 Answers 2

4 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

4 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related