if forking == 0 {
			ForkLock.Lock()
		}
	}

	forking++
}

// releaseForkLock releases the conceptual write lock on ForkLock
// acquired by acquireForkLock.
func releaseForkLock() {
	forkingLock.Lock()
	defer forkingLock.Unlock()

	if forking <= 0 {
		panic("syscall.releaseForkLock: negative count")
	}

	forking--

	if forking == 0 {
		// No more conceptual write locks.

	}
	_, 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()

	if err = forkExecPipe(p[:]); err != nil {
		releaseForkLock()
		return 0, err
	}

	// Kick off child.
	pid, err1 = forkAndExecInChild(argv0p, argvp, envvp, chroot, dir, attr, sys, p[1])
	if err1 != 0 {
		Close(p[0])
		Close(p[1])
		releaseForkLock()
		return 0, Errno(err1)
	}
	releaseForkLock()

	// Read child error status from pipe.
	Close(p[1])
	for {