cc -pthread  -Wall -Wextra -Werror=implicit-function-declaration dirent/readdir_r.c -o dirent/readdir_r -D_GNU_SOURCE -D_BSD_SOURCE -D_ALL_SOURCE -D_DEFAULT_SOURCE -lm -lpthread -lrt -lintl -liconv
dirent/readdir_r.c: In function ‘main’:
dirent/readdir_r.c:25:27: error: implicit declaration of function ‘readdir_r’; did you mean ‘readdir’? [-Wimplicit-function-declaration]
   25 |         while ( !(errno = readdir_r(dir, buffer, &entry)) && entry )
      |                           ^~~~~~~~~
      |                           readdir