cc -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations wchar/putwc.c -o wchar/putwc -D_POSIX_C_SOURCE=202405L -lm -lpthread -lrt -lintl -liconv
wchar/putwc.c:5:34: error: ‘putwc’ undeclared here (not in a function)
    5 | wint_t (*foo)(wchar_t, FILE *) = putwc;
      |                                  ^~~~~