7 Unexported Primitive Functions
Parts of the ffi/unsafe library are implemented by the Racket built-in '#%foreign module. The '#%foreign module is not intended for direct use, but it exports the following procedures. If you find any of these useful, please let us know.
| (ffi-obj objname lib) → any |
| objname : (or/c string? bytes? symbol?) |
| lib : (or/c ffi-lib? path-string? #f) |
Pulls out a foreign object from a library, returning a Racket value
that can be used as a pointer. If a name is provided instead of a
foreign-library value, ffi-lib is used to create a library
object.
| (ffi-obj? x) → boolean? |
| x : any/c |
| (ffi-obj-lib obj) → ffi-lib? |
| obj : ffi-obj? |
| (ffi-obj-name obj) → string? |
| obj : ffi-obj? |
A predicate for objects returned by ffi-obj, and accessor
functions that return its corresponding library object and name.
These values can also be used as C pointer objects.
| (ctype-basetype type) → (or/c ctype? #f) |
| type : ctype? |
| (ctype-scheme->c type) → procedure? |
| type : ctype? |
| (ctype-c->scheme type) → procedure? |
| type : ctype? |
Accessors for the components of a C type object, made by
make-ctype. The ctype-basetype selector returns a
symbol for primitive types that names the type, a list of ctypes for
cstructs, and another ctype for user-defined ctypes.
| (ffi-call ptr in-types out-type [abi]) → any |
| ptr : any/c |
| in-types : (listof ctype?) |
| out-type : ctype? |
| abi : (or/c symbol/c #f) = #f |
The primitive mechanism that creates Racket “callout” values. The
given ptr (any pointer value, including ffi-obj
values) is wrapped in a Racket-callable primitive function that uses
the types to specify how values are marshaled.
The optional abi argument determines the foreign ABI that is used. #f or 'default will use a platform-dependent default; other possible values are 'stdcall and 'sysv (the latter corresponds to “cdecl”). This is especially important on Windows, where most system functions are 'stdcall, which is not the default.
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| proc : any/c | |||||||||||||||||||||||||||||||||||
| in-types : any/c | |||||||||||||||||||||||||||||||||||
| out-type : any/c | |||||||||||||||||||||||||||||||||||
| abi : (or/c symbol/c #f) = #f | |||||||||||||||||||||||||||||||||||
| atomic? : any/c = #f |
The symmetric counterpart of ffi-call. It receives a Racket
procedure and creates a callback object, which can also be used as a
pointer. This object can be used as a C-callable function, which
invokes proc using the types to specify how values are
marshaled.
| (ffi-callback? x) → boolean? |
| x : any/c |
A predicate for callback values that are created by ffi-callback.