cc -pthread  -Wall -Wextra -Werror=implicit-function-declaration wchar/putwchar.c -o wchar/putwchar -D_GNU_SOURCE -D_BSD_SOURCE -D_ALL_SOURCE -D_DEFAULT_SOURCE -lm -lpthread -lrt -lintl -liconv
wchar/putwchar.c: In function ‘main’:
wchar/putwchar.c:15:14: error: implicit declaration of function ‘putwchar’; did you mean ‘putchar’? [-Wimplicit-function-declaration]
   15 |         if ( putwchar(L'x') == WEOF )
      |              ^~~~~~~~
      |              putchar
wchar/putwchar.c:15:29: warning: comparison of integer expressions of different signedness: ‘int’ and ‘unsigned int’ [-Wsign-compare]
   15 |         if ( putwchar(L'x') == WEOF )
      |                             ^~
wchar/putwchar.c:21:15: error: implicit declaration of function ‘fgetws’; did you mean ‘fgets’? [-Wimplicit-function-declaration]
   21 |         if ( !fgetws(buf, sizeof(buf)/sizeof(buf[0]), stdin) )
      |               ^~~~~~
      |               fgets