0. #lang racket/base
1.  
2. (require ffi/unsafe
3.          racket/list)
4.  
5. (define sdl-lib (ffi-lib "libSDL2" '("0" #f)))
6.  
7. (define (get-ffi-vararg name lib ret-type . args)
8.   (lambda rest
9.   (define c-rest (map (lambda (x)
10.                          (cond [(and (integer? x) (exact? x)) _int]
11.                                [(and (number? x) (real? x))   _double*]
12.                                [(string? x)  _string]
13.                                [(bytes? x)   _bytes]
14.                                [(symbol? x)  _symbol]
15.                                [else (error 'get-ffi-vararg
16.                                             "don't know how to deal with ~e" x)]))
17.                        rest))
18.     (apply (get-ffi-obj name lib (_cprocedure (drop (append args c-rest) (length args)) ret-type)) rest)))
19.  
20. (define SDL_SetError (get-ffi-vararg "SDL_SetError" sdl-lib _void  _string))
21. (SDL_SetError)
22.  
23. (define SDL_GetError (get-ffi-obj "SDL_GetError" sdl-lib (_cprocedure '() _string)))
24. (displayln (SDL_GetError))

=>

eval:2:0: ?: access disallowed by code inspector to

protected variable from module:

"/home/pasterack/racket68/collects/ffi/unsafe.rkt"

at: ffi-lib

in: get-ffi-lib

eval:3:0: _double*: access disallowed by code inspector to

protected variable from module: '#%foreign

in: _double*

eval:4:0: _void: access disallowed by code inspector to

protected variable from module: '#%foreign

in: _void

SDL_SetError: undefined;

cannot reference an identifier before its definition

in module: 'm

eval:6:0: get-ffi-obj: access disallowed by code inspector

to protected variable from module:

"/home/pasterack/racket68/collects/ffi/unsafe.rkt"

in: get-ffi-obj

SDL_GetError: undefined;

cannot reference an identifier before its definition

in module: 'm