cc -pthread   -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations fcntl/F_OWNER_PGRP.c -o fcntl/F_OWNER_PGRP -D_POSIX_C_SOURCE=202405L -lm -lpthread -lrt  -lgdbm_compat -lcrypt -latomic
fcntl/F_OWNER_PGRP.c:2:17: error: ‘F_OWNER_PGRP’ undeclared here (not in a function)
    2 | int const foo = F_OWNER_PGRP;
      |                 ^~~~~~~~~~~~