Socket::AncillaryData.unix_rights

static VALUE
ancillary_s_unix_rights(int argc, VALUE *argv, VALUE klass)
{
    VALUE result, str, ary;
    int i;

    ary = rb_ary_new();

    for (i = 0 ; i < argc; i++) {
        VALUE obj = argv[i];
        if (!RB_TYPE_P(obj, T_FILE)) {
            rb_raise(rb_eTypeError, "IO expected");
        }
        rb_ary_push(ary, obj);
    }

    str = rb_str_buf_new(sizeof(int) * argc);

    for (i = 0 ; i < argc; i++) {
        VALUE obj = RARRAY_AREF(ary, i);
        rb_io_t *fptr;
        int fd;
        GetOpenFile(obj, fptr);
        fd = fptr->fd;
        rb_str_buf_cat(str, (char *)&fd, sizeof(int));
    }

    result = ancdata_new(AF_UNIX, SOL_SOCKET, SCM_RIGHTS, str);
    rb_ivar_set(result, rb_intern("unix_rights"), ary);
    return result;
}