callbackMutex.Lock()
	callbackToken++
	i := callbackToken
	callbackFuncs[i] = f
	callbackMutex.Unlock()

	// Pass the address of i because the C function was written to
	// take a pointer.  We could pass an int if we felt like
	// rewriting the C code.
	C.callback(unsafe.Pointer(&i))

	callbackMutex.Lock()
	delete(callbackFuncs, i)
	callbackMutex.Unlock()
}

//export goCallback

of an interface type or of elements of a composite type remains unchanged:
</p>

<pre>
// A Mutex is a data type with two methods, Lock and Unlock.
type Mutex struct         { /* Mutex fields */ }
func (m *Mutex) Lock()    { /* Lock implementation */ }
func (m *Mutex) Unlock()  { /* Unlock implementation */ }

// NewMutex has the same composition as Mutex but its method set is empty.
type NewMutex Mutex

	fw *flate.Writer
}

func (w *pooledFlateWriter) Write(p []byte) (n int, err error) {
	w.mu.Lock()
	defer w.mu.Unlock()
	if w.fw == nil {
		return 0, errors.New("Write after Close")
	}
	return w.fw.Write(p)
}

func (w *pooledFlateWriter) Close() error {
	w.mu.Lock()
	defer w.mu.Unlock()
	var err error
	if w.fw != nil {
		err = w.fw.Close()
		flateWriterPool.Put(w.fw)
		w.fw = nil
	}

// pthread_mutex_t mu;
// int nts = 0;
// int all_done = 0;
//
// static void *aFn(void *vargp) {
//   int done = 0;
//   while (!done) {
//     usleep(100);
//     pthread_mutex_lock(&mu);
//     done = all_done;
//     pthread_mutex_unlock(&mu);
//   }
//   return NULL;
// }
//
// void trial(int argc) {
//   int i;
//   nts = argc;
//   t = calloc(nts, sizeof(pthread_t));
//   pthread_mutex_init(&mu, NULL);

of an interface type or of elements of a composite type remains unchanged:
</p>

<pre>
// A Mutex is a data type with two methods, Lock and Unlock.
type Mutex struct         { /* Mutex fields */ }
func (m *Mutex) Lock()    { /* Lock implementation */ }
func (m *Mutex) Unlock()  { /* Unlock implementation */ }

// NewMutex has the same composition as Mutex but its method set is empty.
type NewMutex Mutex

</p>

<p class="rule">
For any call to <code>l.RLock</code> on a <code>sync.RWMutex</code> variable <code>l</code>,
there is an <i>n</i> such that the <i>n</i>th call to <code>l.Unlock</code>
is synchronized before the return from <code>l.RLock</code>,
and the matching call to <code>l.RUnlock</code> is synchronized before the return from call <i>n</i>+1 to <code>l.Lock</code>.
</p>

<p class="rule">

Austin Clements <******@****.***> 1684423194 -0400

pkg syscall (darwin-arm64), const SYS_PSYNCH_RW_RDLOCK = 306
pkg syscall (darwin-arm64), const SYS_PSYNCH_RW_RDLOCK ideal-int
pkg syscall (darwin-arm64), const SYS_PSYNCH_RW_UNLOCK = 308
pkg syscall (darwin-arm64), const SYS_PSYNCH_RW_UNLOCK ideal-int
pkg syscall (darwin-arm64), const SYS_PSYNCH_RW_UNLOCK2 = 309
pkg syscall (darwin-arm64), const SYS_PSYNCH_RW_UNLOCK2 ideal-int

pkg syscall (freebsd-arm64), const LOCK_EX = 2
pkg syscall (freebsd-arm64), const LOCK_EX ideal-int
pkg syscall (freebsd-arm64), const LOCK_NB = 4
pkg syscall (freebsd-arm64), const LOCK_NB ideal-int
pkg syscall (freebsd-arm64), const LOCK_SH = 1
pkg syscall (freebsd-arm64), const LOCK_SH ideal-int
pkg syscall (freebsd-arm64), const LOCK_UN = 8
pkg syscall (freebsd-arm64), const LOCK_UN ideal-int

pkg syscall (freebsd-riscv64), const SYS_CLOCK_GETCPUCLOCKID2 = 247 #53466
pkg syscall (freebsd-riscv64), const SYS_CLOCK_GETCPUCLOCKID2 ideal-int #53466
pkg syscall (freebsd-riscv64), const SYS_CLOCK_GETRES = 234 #53466
pkg syscall (freebsd-riscv64), const SYS_CLOCK_GETRES ideal-int #53466
pkg syscall (freebsd-riscv64), const SYS_CLOCK_GETTIME = 232 #53466
pkg syscall (freebsd-riscv64), const SYS_CLOCK_GETTIME ideal-int #53466