5.1 Built-In Types

These types correspond to the native C integer types according to the ABI of the Lisp implementation's host system.

For convenience, the above types are provided as shortcuts for unsigned-char, unsigned-short, unsigned-int, unsigned-long, long-long and unsigned-long-long, respectively.

:long-long and :unsigned-long-long are not supported on all implementations. When those types are not available, the symbol cffi-features:no-long-long is pushed into *features*.

Foreign integer types of specific sizes, corresponding to the C types defined in stdint.h.

On all systems, the :float and :double types represent a C float and double, respectively. On most but not all systems, :float and :double represent a Lisp single-float and double-float, respectively. It is not so useful to consider the relationship between Lisp types and C types as isomorphic, as simply to recognize the relationship, and relative precision, among each respective category.

This type is only supported on SCL.

A foreign pointer to an object of any type, corresponding to void *. You can optionally specify type of pointer (e.g. (:pointer :char)). Although CFFI won't do anything with that information yet, it is useful for documentation purposes.

No type at all. Only valid as the return type of a function.