No you can't gracefully handle all fatal errors. The shutdown function will be called after *some* fatal errors but not all of them. See the bug I reported here for more information: http://bugs.php.net/bug.php?id=54195
~Hannes On 9 March 2011 16:12, Ferenc Kovacs <i...@tyrael.hu> wrote: > FYI you can gracefully handle every error. even the non-recoverable ones. > if you check my library you can test it also, I have an example file for > every non recoverable error (E_PARSE, E_CORE_ERROR, etc.). > > from my point of view, every userland error should be catchable from > userland. > the max execution time servers two purpose: > - it saves you from shooting you in the leg (will abort an infinite loop > for example) > - it could be used as a tool by the sysadmin to restrict the cpu usage in a > shared hosting environment. > the ability to execute code via register_shutdown_function after the > "Maximum execution time exceeded" fatal error thrown by the engine makes the > second point void (except if you disable the register_shutdown_function, > which you would do of course in a shared environment). > > so I think that it should be only used for the first problem, in which case > it could be catchable IMO, because it doesn't leave the engine in an > unstable state. > > Tyrael > > On Wed, Mar 9, 2011 at 3:53 PM, Hannes Landeholm <landeh...@gmail.com>wrote: > >> That's not a problem. Timeouts should be non-recoverable IMO as it's a >> serious problem and I think most PHP developers would agree with this. >> Making errors "recoverable" is difficult to implement, could have >> performance penalties and be conceptually wrong when the state is defined as >> "never allowed to happen". >> >> What I'm concerned about is that all problems should be able to be handled >> gracefully from the register_shutdown_function like showing an informative >> page, setting HTTP status, logging the problem, sending an error report, >> etc. Not all fatal errors can be caught this way, including script timeout. >> >> ~Hannes >> >> >> On 9 March 2011 15:39, Ferenc Kovacs <i...@tyrael.hu> wrote: >> >>> no, it only means that you cant return to the original scope and continue >>> the execution of your script. >>> as you can't throw exceptions also, because your code is running without >>> a stack frame. >>> you can check out the https://github.com/Tyrael/php-error-handler its a >>> little class which operates with register_shutdown_function to allow >>> handling non-recoverable errors before halting. >>> there are too many case in the php src where non-recoverable errors are >>> triggered for non fatal problems. >>> that should be changed, so open a bugreport if you think you found one, >>> where isn't neccessary to halt the execution. >>> >>> Tyrael >>> >>> >>> On Wed, Mar 9, 2011 at 3:30 PM, Hannes Landeholm <landeh...@gmail.com>wrote: >>> >>>> You mean the shutdown function is called and 1 nanosecond later PHP >>>> crashes >>>> so you don't have time to do anything? >>>> >>>> ~Hannes >>>> >>>> On 9 March 2011 15:27, David Muir <davidkm...@gmail.com> wrote: >>>> >>>> > Hmm, I think I worded that poorly. >>>> > A function registered with register_shutdown_function does execute >>>> when >>>> > the max_execution_time is exceeded. >>>> > What it doesn't let you do is to recover in the same way an error >>>> > handler would let you. >>>> > >>>> > David >>>> > >>>> > On 09/03/11 22:56, Hannes Landeholm wrote: >>>> > > I second making time limit reached catchable. All non catchable >>>> fatal >>>> > errors >>>> > > are a problem for me. I need to handle problems gracefully to ensure >>>> the >>>> > > stability of production systems instead of PHP just killing itself >>>> > without >>>> > > warning. I just reported a similar issue: >>>> > > http://bugs.php.net/bug.php?id=54195 >>>> > > >>>> > > A simple way to implement this would be to register a function that >>>> would >>>> > be >>>> > > called N seconds before the script would timeout. >>>> > > >>>> > > register_timeout_handler(2, function() { die("PHP timed out."); }); >>>> > > >>>> > > It would be called just as a shutdown function - in fact I'd like to >>>> use >>>> > the >>>> > > same function as my shutdown function and get the error with >>>> > > error_get_last(). Of course set_time_limit(0) could be used in this >>>> > function >>>> > > to prevent the timeout of the timeout handler. This does not >>>> "prevent" >>>> > > timeout since set_time_limit could have been called by the script >>>> before >>>> > the >>>> > > timeout anyway. >>>> > > >>>> > > On that note I also miss a function which returns the time the >>>> script can >>>> > > keep running for. If that calculate needs to be calculated to >>>> implemented >>>> > to >>>> > > implement this, why not make the value available to the PHP script? >>>> > > >>>> > > ~Hannes >>>> > > >>>> > > On 9 March 2011 02:30, David Muir <davidkm...@gmail.com> wrote: >>>> > > >>>> > >> Although it doesn't let you recover from a timeout, you could use >>>> > >> register_shutdown_function to gracefully exit after a fatal error. >>>> > >> >>>> > >> register_shutdown_function(function(){ >>>> > >> $error = error_get_last(); >>>> > >> if($error && $error['type'] === E_ERROR){ >>>> > >> echo 'PHAIL! Oh noes, something went wrong!'; >>>> > >> // do whatever else you need to do before quitting >>>> > >> } >>>> > >> }); >>>> > >> >>>> > >> Cheers, >>>> > >> David >>>> > >> >>>> > >> On 08/03/11 22:39, Pierre Joye wrote: >>>> > >>> hi, >>>> > >>> >>>> > >>> is not the goal of this setting to prevent that a script runs >>>> longer >>>> > >>> than a given time? A catchable error will prevent that to happen. >>>> > >>> >>>> > >>> On Tue, Mar 8, 2011 at 2:05 PM, Sebastian Bergmann < >>>> sebast...@php.net> >>>> > >> wrote: >>>> > >>>> Could set_time_limit() be changed in such a way that it triggers >>>> a >>>> > >>>> catchable fatal error instead of a fatal error? Thanks! >>>> > >>>> >>>> > >>>> -- >>>> > >>>> Sebastian Bergmann Co-Founder and Principal >>>> > >> Consultant >>>> > >>>> http://sebastian-bergmann.de/ >>>> > >> http://thePHP.cc/ >>>> > >>>> -- >>>> > >>>> PHP Internals - PHP Runtime Development Mailing List >>>> > >>>> To unsubscribe, visit: http://www.php.net/unsub.php >>>> > >>>> >>>> > >>>> >>>> > >>> >>>> > >> >>>> > >> -- >>>> > >> PHP Internals - PHP Runtime Development Mailing List >>>> > >> To unsubscribe, visit: http://www.php.net/unsub.php >>>> > >> >>>> > >> >>>> > >>>> > >>>> > -- >>>> > PHP Internals - PHP Runtime Development Mailing List >>>> > To unsubscribe, visit: http://www.php.net/unsub.php >>>> > >>>> > >>>> >>> >>> >> >
