php man page for mb_substitute_character

MB_SUBSTITUTE_CHARACTER(3)						 1						MB_SUBSTITUTE_CHARACTER(3)

mb_substitute_character - Set/Get substitution character

SYNOPSIS
       mixed mb_substitute_character ([mixed  $substrchar = mb_substitute_character()])

DESCRIPTION
	Specifies a substitution character when input character encoding is invalid or character code does not exist in output character encoding.
       Invalid characters may be substituted NULL (no output), string or integer value (Unicode character code value).

	This setting affects mb_convert_encoding(3), mb_convert_variables(3), mb_output_handler(3), and mb_send_mail(3).

PARAMETERS
	      o $substrchar
		- Specify the Unicode value as an integer, or as one of the following strings:

		     o "none": no output

		     o "long": Output character code value (Example: U+3000, JIS+7E7E)

		     o "entity": Output character entity (Example: )

RETURN VALUES
	If $substchar is set, it returns TRUE for success, otherwise returns FALSE. If $substchar is not set, it returns the current setting.

EXAMPLES
       Example #1

	      mb_substitute_character(3) example

	      <?php
	      /* Set with Unicode U+3013 (GETA MARK) */
	      mb_substitute_character(0x3013);

	      /* Set hex format */
	      mb_substitute_character("long");

	      /* Display current setting */
	      echo mb_substitute_character();
	      ?>

PHP Documentation Group 												MB_SUBSTITUTE_CHARACTER(3)