cc -O2 -pipe -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations unistd/_XOPEN_UUCP.c -o unistd/_XOPEN_UUCP -D_POSIX_C_SOURCE=202405L  -lm -lpthread -lrt  -lstdthreads -lcrypt
unistd/_XOPEN_UUCP.c:4:2: error: "_XOPEN_UUCP is not defined"
    4 | #error "_XOPEN_UUCP is not defined"
      |  ^
1 error generated.