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Is there a way to make the code continue (not exit) when you get a fatal error in PHP? For example I get a timeout fatal error and I want whenever it happens to skip this task and the continue with others. In this case the script exits.

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  • If you are running a PHP script which requires say more than 2-4 seconds to execute, then you are doing something majorly wrong. Use another technology or change your workflow. Commented Jul 17, 2009 at 10:32
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    @Alec Smart I don't agree with that - cron jobs etc regularly take longer than a few seconds. Maybe it would run faster in C++, but then you'd have to hire a C++ programmer... Commented Jul 17, 2009 at 11:12

6 Answers 6

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There is a hack using output buffering that will let you log certain fatal errors, but there's no way to continue a script after a fatal error occurs - that's what makes it fatal!

If your script is timing out you can use set_time_limit() to give it more time to execute.

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"Fatal Error", as it's name indicates, is Fatal : it stop the execution of the script / program.

If you are using PHP to generate web pages and get a Fatal error related to max_execution_time which, by defaults, equals 30 seconds, you are certainly doing something that really takes too mych time : users won't probably wait for so long to get the page.

If you are using PHP to do some heavy calculations, not in a webpage (but via CLI, or a cron, or stuff like that), you can set another (greater) value for max_execution_time. You have two ways of doing that :

First is to modify php.ini, to set this value (it's already in the file ; just edit the property's value). Problem is it'll modify it also for the web server, which is bad (this is a security measure, after all). Better way is to create a copy of php.ini, called, for instance, phpcli.ini, and modify this file. Then, use it when invoking php :

php -c phpcli.ini myscript.php 

This'll work great if you have many properties you need to configure for CLI execution. (Like memory_limit, which often has to be set to a higher value for long-running batches)

The other way is to define a different value for max_execution_time when you invoke php, like this :

php -d max_execution_time=60 myscript.php 

This is great if you launch this via the crontab, for instance.

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It depends on the exact error type. You can catch errors by creating your own error handler. See the documentation on set_error_handler(), but not all types of errors can be caught. Look at the timeout error you get and see what type it is. If it is one of E_ERROR, E_PARSE, E_CORE_ERROR, E_CORE_WARNING, E_COMPILE_ERROR or E_COMPILE_WARNING then you cannot catch it with an error handler. If it another type then you can. Catch it with the error handler and simply return.

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If you have a suitable PHP version (PHP>=5.2 for error_get_last) you can try the technique described here which uses register_shutdown_function and error_get_last.

This won't allow you to "continue" when you get a fatal error, but it at least allows you to log the error (and perhaps send a warning email) before displaying a custom error page to the user.

It works something like this:

function fatalErrorHandler() { $lastError = error_get_last(); if (isset($lastError["type"]) && $lastError["type"]==E_ERROR) { // do something with the fatal error } } ... register_shutdown_function('fatalErrorHandler'); 


A few points:

  • you can use ob_clean() to remove any content that was generated prior to the fatal error.
  • it's a really bad idea to do anything to intensive in the shutdown handler, this technique is about graceful failure rather than recovery.
  • whatever you do, don't try to log the error to a database ... what if it was a database timeout that caused the fatal error?
  • for some reason I've had problems getting this technique to work 100% of the time when developing in Windows using WAMP.

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The most simple answer I can give you is this function: http://php.net/manual/en/function.pcntl-fork.php

In more detail, what you can do is:

  • Fork the part of the process you think might or might not cause a fatal error (i.e. the bulk of your code)
  • The script that forks the process should be a very simple script.

For example this is something that I would do with a job queue that I have:

<?php // ... load stuff regarding the job queue while ($job = $queue->getJob()) { $pid = pcntl_fork(); switch ($pid) { case -1: echo "Fork failed"; break; case 0: // do your stuff here echo "Child finished working"; break; default: echo "Waiting for child..."; pcntl_wait($status); // check the status using other pcntl* functions if you want break; } } 

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Is there a way then to limit the execution time of an function but not all script? For example

function blabla() { return "yes"; } 

to make it so that if it is not executed in 25 seconds to return no;

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