C Data Handles

(PHP 7 >= 7.4.0)


FFI\CData objects can be used in a number of ways as a regular PHP data:

  • C data of scalar types can be read and assigned via the $cdata property, e.g. $x = FFI::new('int'); $x->cdata = 42;
  • C struct and union fields can be accessed as regular PHP object property, e.g. $cdata->field
  • C array elements can be accessed as regular PHP array elements, e.g. $cdata[$offset]
  • C arrays can be iterated using foreach statements.
  • C arrays can be used as arguments of count().
  • C pointers can be dereferenced as arrays, e.g. $cdata[0]
  • C pointers can be compared using regualar comparison operators (<, <=, ==, !=, >=, >).
  • C pointers can be incremented and decremented using regular +/-/ ++/–- operations, e.g. $cdata += 5
  • C pointers can be subtracted from another using regular - operations.
  • C pointers to functions can be called as a regular PHP closure, e.g. $cdata()
  • Any C data can be duplicated using the clone operator, e.g. $cdata2 = clone $cdata;
  • Any C data can be visualized using var_dump(), print_r(), etc.

Note: Noteable limitations are that FFI\CData instances do not support isset(), empty() and unset(), and that wrapped C structs and unions do not implement Traversable.


FFI\CData {