foreign-funcall

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Syntax

— Macro: foreign-funcall name-and-options &rest arguments ⇒ return-value

arguments ::= { arg-type arg }* [return-type] name-and-options ::= name | ( name &key library convention)

Arguments and Values

name: A Lisp string.
arg-type: A foreign type.
arg: An argument of type arg-type.
return-type: A foreign type, :void by default.
return-value: A lisp object.
library: A lisp symbol; not evaluated.
convention: One of :cdecl (default) or :stdcall.

Description

The foreign-funcall macro is the main primitive for calling foreign functions.

Note: The return value of foreign-funcall on functions with a :void return type is still undefined.

Implementation-specific Notes

Corman Lisp does not support foreign-funcall. On implementations that don't support foreign-funcall cffi-sys::no-foreign-funcall will be present in *features*. Note: in these Lisps you can still use the defcfun interface.

Examples

  CFFI> (foreign-funcall "strlen" :string "foo" :int)
  => 3

Given the C code:

  void print_number(int n)
  {
      printf("N: %d\n", n);
  }

  CFFI> (foreign-funcall "print_number" :int 123456)
  -| N: 123456
  => NIL

Or, equivalently:

  CFFI> (foreign-funcall "print_number" :int 123456 :void)
  -| N: 123456
  => NIL

  CFFI> (foreign-funcall "printf" :string (format nil "%s: %d.~%")
                         :string "So long and thanks for all the fish"
                         :int 42 :int)
  -| So long and thanks for all the fish: 42.
  => 41