Edit report at https://bugs.php.net/bug.php?id=61091&edit=1
ID: 61091
Updated by: ras...@php.net
Reported by: chealer at gmail dot com
Summary: User-defined error handler run despite at sign (@)
error control operator
Status: Not a bug
Type: Bug
Package: *General Issues
PHP Version: 5.3.10
Block user comment: N
Private report: N
New Comment:
It says, "however you are still able to read the current value of
error_reporting
and act appropriately" followed by "Of particular note is that this value will
be
0 if the statement that caused the error was prepended by the @ error-control
operator."
To me this says quite clearly that error_reporting will be 0 if the @ was used
and that your custom error handler can read this value and "act appropriately."
Previous Comments:
------------------------------------------------------------------------
[2012-02-19 19:49:22] chealer at gmail dot com
Rasmus, the part you quoted is about error_reporting() settings, it merely
mentions the error control operator.
My question was, could you quote where "http://www.php.net/set_error_handler
[...] explains that the user-defined error
handler should check the error_reporting level in order to comply with the '@'
if so desired"?
------------------------------------------------------------------------
[2012-02-15 16:53:06] ras...@php.net
"error_reporting() settings will have no effect and your error handler will be
called regardless - however you are still able to read the current value of
error_reporting and act appropriately. Of particular note is that this value
will
be 0 if the statement that caused the error was prepended by the @
error-control
operator."
------------------------------------------------------------------------
[2012-02-15 16:25:42] chealer at gmail dot com
Thanks rasmus, but I do not see this explanation. Could you quote it?
------------------------------------------------------------------------
[2012-02-15 03:45:12] ras...@php.net
This is very much by design and definitely won't be changed since that would
break all sorts of code. It is also explicitly documented at
http://www.php.net/set_error_handler which explains that the user-defined error
handler should check the error_reporting level in order to comply with the '@'
if
so desired.
------------------------------------------------------------------------
[2012-02-15 03:06:15] chealer at gmail dot com
Description:
------------
The at sign operator allows to "ignore" error messages, as explained in
http://ca3.php.net/manual/en/language.operators.errorcontrol.php
When prepended to an expression in PHP, any error messages that might be
generated by that expression will be ignored.
However, user-defined error handlers registered with set_error_handler() are
nevertheless run when @ is used, which often causes such messages to show, as
in the below example, where a custom error handler is used to customize the
display of error messages.
As http://ca3.php.net/manual/en/language.operators.errorcontrol.php#98895 and
http://ca3.php.net/manual/en/language.operators.errorcontrol.php#85042 show,
this problem is not new. This behavior appears to be by design, and might be
wanted in some cases.
Therefore, please either:
Stop calling user-defined error handlers when suppressing errors. This needs
serious consideration for backwards-compatibility.
Allow specifying whether user-defined error handlers should be called when
suppressing errors.
Make the documentation reflect the current state of things.
Test script:
---------------
<?php
function myErrorHandler($errno, $errstr) {
switch ($errno) {
case E_USER_ERROR:
echo "<b>My ERROR</b> [$errno] $errstr<br />\n";
echo " Fatal error on line $errline in file $errfile";
echo ", PHP " . PHP_VERSION . " (" . PHP_OS . ")<br />\n";
echo "Aborting...<br />\n";
exit(1);
break;
case E_USER_WARNING:
echo "<b>My WARNING</b> [$errno] $errstr<br />\n";
break;
case E_USER_NOTICE:
echo "<b>My NOTICE</b> [$errno] $errstr<br />\n";
break;
default:
echo "Unknown error type: [$errno] $errstr<br />\n";
break;
}
}
// function to test the error handling
function scale_by_log($vect, $scale)
{
if (!is_numeric($scale) || $scale <= 0) {
trigger_error("log(x) for x <= 0 is undefined, you used: scale =
$scale", E_USER_ERROR);
}
if (!is_array($vect)) {
trigger_error("Incorrect input vector, array of values expected",
E_USER_WARNING);
return null;
}
$temp = array();
foreach($vect as $pos => $value) {
if (!is_numeric($value)) {
trigger_error("Value at position $pos is not a number, using 0
(zero)", E_USER_NOTICE);
$value = 0;
}
$temp[$pos] = log($scale) * $value;
}
return $temp;
}
$a = array(2, 3, "foo", 5.5, 43.3, 21.11);
/* Value at position $pos is not a number, using 0 (zero) */
scale_by_log($a, M_PI);
@scale_by_log($a, M_PI);
set_error_handler("myErrorHandler");
@scale_by_log($a, M_PI);
?>
Expected result:
----------------
Notice: Value at position 2 is not a number, using 0 (zero) in
/var/www/atoperator.php on line 42
Call Stack:
0.0005 339192 1. {main}() /var/www/atoperator.php:0
0.0005 339836 2. scale_by_log(array (0 => 2, 1 => 3, 2 => 'foo', 3 =>
5.5, 4 => 43.3, 5 => 21.11), 3.1415926535898) /var/www/atoperator.php:55
0.0006 340648 3. trigger_error('Value at position 2 is not a number,
using 0 (zero)', 1024) /var/www/atoperator.php:42
Actual result:
--------------
Notice: Value at position 2 is not a number, using 0 (zero) in
/var/www/atoperator.php on line 42
Call Stack:
0.0005 339192 1. {main}() /var/www/atoperator.php:0
0.0005 339836 2. scale_by_log(array (0 => 2, 1 => 3, 2 => 'foo', 3 =>
5.5, 4 => 43.3, 5 => 21.11), 3.1415926535898) /var/www/atoperator.php:55
0.0006 340648 3. trigger_error('Value at position 2 is not a number,
using 0 (zero)', 1024) /var/www/atoperator.php:42
<b>My NOTICE</b> [1024] Value at position 2 is not a number, using 0 (zero)<br
/>
------------------------------------------------------------------------
--
Edit this bug report at https://bugs.php.net/bug.php?id=61091&edit=1
