iconv

static VALUE
iconv_s_iconv(int argc, VALUE *argv, VALUE self)
{
    struct iconv_env_t arg;

    if (argc < 2)               /* needs `to' and `from' arguments at least */
        rb_raise(rb_eArgError, "wrong number of arguments (%d for %d)", argc, 2);

    arg.argc = argc -= 2;
    arg.argv = argv + 2;
    arg.append = rb_ary_push;
    arg.ret = rb_ary_new2(argc);
    arg.cd = iconv_create(argv[0], argv[1], NULL, &arg.toidx);
    return rb_ensure(iconv_s_convert, (VALUE)&arg, iconv_free, ICONV2VALUE(arg.cd));
}