cc -pthread  -Wall -Wextra -Werror=implicit-function-declaration wchar/wscanf.c -o wchar/wscanf -D_GNU_SOURCE -D_BSD_SOURCE -D_ALL_SOURCE -D_DEFAULT_SOURCE -lm -lpthread -lrt -lintl -liconv
wchar/wscanf.c: In function ‘main’:
wchar/wscanf.c:15:14: error: implicit declaration of function ‘fputws’; did you mean ‘fputs’? [-Wimplicit-function-declaration]
   15 |         if ( fputws(L"hello world 42", stdout) == EOF )
      |              ^~~~~~
      |              fputs
wchar/wscanf.c:22:19: error: implicit declaration of function ‘wscanf’; did you mean ‘vscanf’? [-Wimplicit-function-declaration]
   22 |         int ret = wscanf(L"hello %5ls %d", world, &value);
      |                   ^~~~~~
      |                   vscanf