set_error_handler not working on some servers

Cerddaf

I've got a user error handler which has been working fine on a dozen or so websites on 3 different hosting companies.

Trying it on the 4th one however the set_error_handler command appears not to actually do anything.

Is this a configuration option that can be turned off?

dagon

its possible for a host to disable any php function, best option is to ask them

Cerddaf

I'm still waiting for an answer!

dagon

well wait, you don't expect us to know how your host installed php do you :-)

Cerddaf

They got back to me, and were quite helpful.

Problem is (as you say) that their PHP is built differently somehow.

The other servers that I've run this error handler on will let the error handler catch runtime type errors (wrong parameter passed etc) and also catch format errors (eg a line such as "silly code = ")

These servers will only catch the runtime type errors (wrong parameter passed etc) . They won't catch format errors ("silly code = ;"). They just write to the error log, and then die leaving no trace.

So the interesting question is why?
One server is running PHP 5.2.8, the other runs 5.2.6, so that should not be a big difference, and the error handling stuff tends to be fairly stable.

I've asked them to check with their techies.
But if anyone knows about any buildtime options that can cause this, then I'd be interested.

for example, do some versions of PHP do "compile type" checks differently.

NogDog

They probably have display_errors turned off at the system level. Since parse errors happen before any code in the script is actually processed, they only get displayed if display_errors is turned on at the system level (php.ini) or the directory level (.htaccess). Turning it on within the script won't help.

Cerddaf

Interesting.

On the other servers the parse errors do get reported, eg

"Parse error: syntax error, unexpected '=' in /home/fhlinux182/t/XXXXXXXXXX/user/htdocs/test.php on line 53 ""

NogDog

Yep, like I said, it depends on whether or not display_errors is turned on in the PHP configuration.

PS: From a security standpoint, no production server should have display errors turned on, as it can reveal information about your scripts you might not want certain people to see. Parse errors should be found in your development server and/or your IDE/editor with built-in parse-checking.