will not be touched by the parsing function if they are not
passed to it.
/ - use SEPARATE_ZVAL_IF_NOT_REF() on the parameter it follows
- ! - the parameter it follows can be of specified type or NULL (only applies
- to 'a', 'o', 'O', 'r', and 'z'). If NULL is passed, the results
- pointer is set to NULL as well.
+ ! - the parameter it follows can be of specified type or NULL (applies
+ to all specifiers except for 'b', 'l', and 'd'). If NULL is passed, the
+ results pointer is set to NULL as well.
& - alternate format (currently used for 's' only to specify a converter to
use when converting from Unicode strings)
^ - returns original string type before conversion (only for 's' and 'u'