#35101 [NEW]: A custom handler set with set_error_handler() cannot be unset/removed

From: mfischer@php.net Operating system: Any PHP version: 5CVS-2005-11-04 (CVS) PHP Bug Type: Scripting Engine problem Bug description: A custom handler set with set_error_handler() cannot be unset/removed Description: ------------ A custom error handler set with set_error_handler() cannot be removed. The documentation says that the return value of set_error_handler() is the previous error handler. In case of no previous error handler, NULL is returned. However set_error_handler() cannot be called with NULL to restore the PHP default error handler. This results in the following: $ php -r 'set_error_handler(NULL);' Warning: set_error_handler() expects argument 1, '', to be a valid callback in Command line code on line 1 Reproduce code: --------------- <?php function handler() { echo "called\n"; } set_error_handler('handler called'); set_error_handler(); ?> Expected result: ---------------- Somehow a way for removing the current error handler and restoring the original behaviour should be possible. Actual result: -------------- handler called -- Edit bug report at http://bugs.php.net/?id=35101&edit=1 -- Try a CVS snapshot (php4): http://bugs.php.net/fix.php?id=35101&r=trysnapshot4 Try a CVS snapshot (php5.0): http://bugs.php.net/fix.php?id=35101&r=trysnapshot50 Try a CVS snapshot (php5.1): http://bugs.php.net/fix.php?id=35101&r=trysnapshot51 Fixed in CVS: http://bugs.php.net/fix.php?id=35101&r=fixedcvs Fixed in release: http://bugs.php.net/fix.php?id=35101&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=35101&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=35101&r=needscript Try newer version: http://bugs.php.net/fix.php?id=35101&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=35101&r=support Expected behavior: http://bugs.php.net/fix.php?id=35101&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=35101&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=35101&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=35101&r=globals PHP 3 support discontinued: http://bugs.php.net/fix.php?id=35101&r=php3 Daylight Savings: http://bugs.php.net/fix.php?id=35101&r=dst IIS Stability: http://bugs.php.net/fix.php?id=35101&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=35101&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=35101&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=35101&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=35101&r=mysqlcfg