wctob
int wctob(wint_t);
num_read = wctob(wc);
ATF_REQUIRE_EQ(wctob(*wcp), EOF);
ATF_REQUIRE_EQ(wctob(WEOF), EOF);
c, btowc(c), (unsigned char)wctob(btowc(c)));
ATF_REQUIRE_EQ(wctob(btowc(c)), c);
ATF_REQUIRE_EQ(wctob(WEOF), EOF);
ATF_REQUIRE_EQ((unsigned char)wctob(i), (wchar_t)i);
} else if (wc != L'\0' && (c = wctob(wc)) != EOF &&