forking int
)

// hasWaitingReaders reports whether any goroutine is waiting
// to acquire a read lock on rw. It is defined in the sync package.
func hasWaitingReaders(rw *sync.RWMutex) bool

// acquireForkLock acquires a write lock on ForkLock.
// ForkLock is exported and we've promised that during a fork
// we will call ForkLock.Lock, so that no other threads create
// new fds that are not yet close-on-exec before we fork.

	err := Pipe(p)
	if err != nil {
		return err
	}
	_, err = fcntl(p[0], F_SETFD, FD_CLOEXEC)
	if err != nil {
		return err
	}
	_, err = fcntl(p[1], F_SETFD, FD_CLOEXEC)
	return err
}

func acquireForkLock() {
	ForkLock.Lock()
}

func releaseForkLock() {
	ForkLock.Unlock()

		return 0, errorspkg.New("both Setctty and Foreground set in SysProcAttr")
	}
	if sys.Setctty && sys.Ctty >= len(attr.Files) {
		return 0, errorspkg.New("Setctty set but Ctty not valid in child")
	}

	acquireForkLock()

	// Allocate child status pipe close on exec.
	if err = forkExecPipe(p[:]); err != nil {
		releaseForkLock()
		return 0, err
	}

	// Kick off child.