cc -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations unistd/getgroups.c -o unistd/getgroups -D_POSIX_C_SOURCE=202405L -lm -lpthread -lrt -lintl -liconv
unistd/getgroups.c:5:29: error: ‘getgroups’ undeclared here (not in a function)
    5 | int (*foo)(int, gid_t []) = getgroups;
      |                             ^~~~~~~~~