cc -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations unistd/pipe2.c -o unistd/pipe2 -D_POSIX_C_SOURCE=202405L  -lm -lpthread  -liconv
unistd/pipe2.c:5:28: error: use of undeclared identifier 'pipe2'; did you mean 'pipe'?
    5 | int (*foo)(int [2], int) = pipe2;
      |                            ^~~~~
      |                            pipe
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/unistd.h:470:6: note: 'pipe' declared here
  470 | int      pipe(int [2]);
      |          ^
unistd/pipe2.c:5:7: error: incompatible function pointer types initializing 'int (*)(int *, int)' with an expression of type 'int (int *)' [-Wincompatible-function-pointer-types]
    5 | int (*foo)(int [2], int) = pipe2;
      |       ^                    ~~~~~
2 errors generated.