The constants below are always available as part of the PHP core.
Note: You may use these constant names in php.ini but not outside of PHP, like in httpd.conf, where you'd use the bitmask values instead.
| Value | Constant | Description | Note | 
|---|---|---|---|
| 1 | 
      E_ERROR 
      (integer)
      | 
     Fatal run-time errors. These indicate errors that can not be recovered from, such as a memory allocation problem. Execution of the script is halted. | |
| 2 | 
      E_WARNING 
      (integer)
      | 
     Run-time warnings (non-fatal errors). Execution of the script is not halted. | |
| 4 | 
      E_PARSE 
      (integer)
      | 
     Compile-time parse errors. Parse errors should only be generated by the parser. | |
| 8 | 
      E_NOTICE 
      (integer)
      | 
     Run-time notices. Indicate that the script encountered something that could indicate an error, but could also happen in the normal course of running a script. | |
| 16 | 
      E_CORE_ERROR 
      (integer)
      | 
     
      Fatal errors that occur during PHP's initial startup. This is like an
      E_ERROR, except it is generated by the core of PHP.
      | 
     |
| 32 | 
      E_CORE_WARNING 
      (integer)
      | 
     
      Warnings (non-fatal errors) that occur during PHP's initial startup.
      This is like an E_WARNING, except it is generated
      by the core of PHP.
      | 
     |
| 64 | 
      E_COMPILE_ERROR 
      (integer)
      | 
     
      Fatal compile-time errors. This is like an E_ERROR,
      except it is generated by the Zend Scripting Engine.
      | 
     |
| 128 | 
      E_COMPILE_WARNING 
      (integer)
      | 
     
      Compile-time warnings (non-fatal errors). This is like an
      E_WARNING, except it is generated by the Zend
      Scripting Engine.
      | 
     |
| 256 | 
      E_USER_ERROR 
      (integer)
      | 
     
      User-generated error message. This is like an
      E_ERROR, except it is generated in PHP code by
      using the PHP function trigger_error().
      | 
     |
| 512 | 
      E_USER_WARNING 
      (integer)
      | 
     
      User-generated warning message. This is like an
      E_WARNING, except it is generated in PHP code by
      using the PHP function trigger_error().
      | 
     |
| 1024 | 
      E_USER_NOTICE 
      (integer)
      | 
     
      User-generated notice message. This is like an
      E_NOTICE, except it is generated in PHP code by
      using the PHP function trigger_error().
      | 
     |
| 2048 | 
      E_STRICT 
      (integer)
      | 
     Enable to have PHP suggest changes to your code which will ensure the best interoperability and forward compatibility of your code. | Since PHP 5 but not included in E_ALL until PHP 5.4.0 | 
    
| 4096 | 
      E_RECOVERABLE_ERROR 
      (integer)
      | 
     
      Catchable fatal error. It indicates that a probably dangerous error
      occurred, but did not leave the Engine in an unstable state. If the error
      is not caught by a user defined handle (see also
      set_error_handler()), the application aborts as it
      was an E_ERROR.
      | 
     Since PHP 5.2.0 | 
| 8192 | 
      E_DEPRECATED 
      (integer)
      | 
     Run-time notices. Enable this to receive warnings about code that will not work in future versions. | Since PHP 5.3.0 | 
| 16384 | 
      E_USER_DEPRECATED 
      (integer)
      | 
     
      User-generated warning message. This is like an
      E_DEPRECATED, except it is generated in PHP code by
      using the PHP function trigger_error().
      | 
     Since PHP 5.3.0 | 
| 32767 | 
      E_ALL 
      (integer)
      | 
     
      All errors and warnings, as supported, except of level
      E_STRICT prior to PHP 5.4.0.
      | 
     32767 in PHP 5.4.x, 30719 in PHP 5.3.x, 6143 in PHP 5.2.x, 2047 previously | 
The above values (either numerical or symbolic) are used to build up a bitmask that specifies which errors to report. You can use the bitwise operators to combine these values or mask out certain types of errors. Note that only '|', '~', '!', '^' and '&' will be understood within php.ini.