php man page for trigger_error

TRIGGER_ERROR(3)							 1							  TRIGGER_ERROR(3)

trigger_error - Generates a user-level error/warning/notice message

SYNOPSIS
       bool trigger_error (string  $error_msg, [int  $error_type = E_USER_NOTICE])

DESCRIPTION
	Used  to  trigger  a  user error condition, it can be used in conjunction with the built-in error handler, or with a user defined function
       that has been set as the new error handler (set_error_handler(3)).

	This function is useful when you need to generate a particular response to an exception at runtime.

PARAMETERS
	      o $error_msg
		- The designated error message for this error. It's limited to 1024 bytes in length. Any additional characters beyond  1024  bytes
		will be truncated.

	      o $error_type
		- The designated error type for this error. It only works with the E_USER family of constants, and will default to E_USER_NOTICE.

RETURN VALUES
	This function returns FALSE if wrong $error_type is specified, TRUE otherwise.

EXAMPLES
       Example #1

	      trigger_error(3) example

	       See set_error_handler(3) for a more extensive example.

	      <?php
	      if ($divisor == 0) {
		  trigger_error("Cannot divide by zero", E_USER_ERROR);
	      }
	      ?>

NOTES
       Warning

	       HTML entities in $error_msg are not escaped. Use htmlentities(3) on the message if the error is to be displayed in a browser.

SEE ALSO
       error_reporting(3), set_error_handler(3), restore_error_handler(3), The error level constants.

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