cc -pthread  -Wall -Wextra -Werror=implicit-function-declaration spawn/posix_spawn_file_actions_addfchdir.c -o spawn/posix_spawn_file_actions_addfchdir -D_GNU_SOURCE -D_BSD_SOURCE -D_ALL_SOURCE -D_DEFAULT_SOURCE -lm -lpthread -lrt -lcrypt -latomic
spawn/posix_spawn_file_actions_addfchdir.c: In function ‘main’:
spawn/posix_spawn_file_actions_addfchdir.c:44:23: error: implicit declaration of function ‘posix_spawn_file_actions_addfchdir’; did you mean ‘posix_spawn_file_actions_addfchdir_np’? [-Wimplicit-function-declaration]
   44 |         if ( (errno = posix_spawn_file_actions_addfchdir(&actions, dirfd)) )
      |                       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      |                       posix_spawn_file_actions_addfchdir_np