cc -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations sys_mman/shm_unlink.c -o sys_mman/shm_unlink -D_POSIX_C_SOURCE=202405L -lm -lpthread -lrt -lintl -liconv
sys_mman/shm_unlink.c:6:28: error: ‘shm_unlink’ undeclared here (not in a function)
    6 | int (*foo)(const char *) = shm_unlink;
      |                            ^~~~~~~~~~