sema  uint32
}

// A Locker represents an object that can be locked and unlocked.
type Locker interface {
	Lock()
	Unlock()
}

const (
	mutexLocked = 1 << iota // mutex is locked
	mutexWoken
	mutexStarving
	mutexWaiterShift = iota

	// Mutex fairness.
	//
	// Mutex can be in 2 modes of operations: normal and starvation.
	// In normal mode waiters are queued in FIFO order, but a woken up waiter

package sha3

// spongeDirection indicates the direction bytes are flowing through the sponge.
type spongeDirection int

const (
	// spongeAbsorbing indicates that the sponge is absorbing input.
	spongeAbsorbing spongeDirection = iota
	// spongeSqueezing indicates that the sponge is being squeezed.
	spongeSqueezing
)

const (
	// maxRate is the maximum size of the internal buffer. SHAKE-256
	// currently needs the largest buffer.
	maxRate = 168

	if e != nil {
		return nil, &PathError{Op: "fork/exec", Path: name, Err: e}
	}

	return newPIDProcess(pid), nil
}

func (p *Process) writeProcFile(file string, data string) error {
	f, e := OpenFile("/proc/"+itoa.Itoa(p.Pid)+"/"+file, O_WRONLY, 0)
	if e != nil {
		return e
	}
	defer f.Close()
	_, e = f.Write([]byte(data))
	return e
}

func (p *Process) signal(sig Signal) error {
	switch p.pidStatus() {

	})
	if err == syscall.ENOENT || (err == nil && !found) {
		return nil, UnknownGroupIdError(strconv.Itoa(gid))
	}
	if err != nil {
		return nil, fmt.Errorf("user: lookup groupid %d: %v", gid, err)
	}
	return buildGroup(&grp), nil
}

func buildGroup(grp *_C_struct_group) *Group {
	g := &Group{
		Gid:  strconv.Itoa(int(_C_gr_gid(grp))),
		Name: _C_GoString(_C_gr_name(grp)),
	}
	return g
}