Re: [Chicken-users] ffi - the right way to return a list holding integers and strings

[felix winkelmann]

On 7/6/07, foobar <address@hidden> wrote:
> Great thanks. Just to be sure i've done it correctly.
> Here is an example on how i would return a list of one string element.
>
> (define return-a-list-with-string-elt
>   (foreign-primitive scheme-object ()
>                    "char str[] = \"hallo\";"
>                    "C_word *sstr = C_alloc(C_SIZEOF_STRING(strlen(str)));"
>                    "C_return(C_h_list(1,C_string2(&sstr,str)));"))
>
> This code works as expected.
> It does hopefully allso not leak memory.

I'd perhaps do it this way:

(foreign-primitive scheme-object ()
 "char *str[] = \"hallo\";"
 "C_word *buf = C_alloc(C_SIZEOF_STRING(strlen(str)) + C_SIZEOF_PAIR);"
 "C_word str = C_string2(&buf, str);"
 "C_return(C_a_i_list(&buf, 1, str));")


cheers,
felix