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