listed in /etc/resolv.conf, or it can use a cgo-based resolver that calls C
library routines such as getaddrinfo and getnameinfo.

On Unix the pure Go resolver is preferred over the cgo resolver, because a blocked DNS
request consumes only a goroutine, while a blocked C call consumes an operating system thread.
When cgo is available, the cgo-based resolver is used instead under a variety of
conditions: on systems that do not let programs make direct DNS requests (OS X),

     */
    void submit(ConditionalExecution<T> execution);

    /**
     * Expand the execution queue worker pool.  This should be called before an execution in the queue is blocked waiting
     * on another execution (e.g. work that submits and waits on other work).
     */
    void expand();

	for name, counts := range cover.Counters {
		blocks := cover.Blocks[name]
		for i := range counts {
			stmts := int64(blocks[i].Stmts)
			total += stmts
			count = atomic.LoadUint32(&counts[i]) // For -mode=atomic.
			if count > 0 {
				active += stmts
			}
			if f != nil {
				_, err := fmt.Fprintf(f, "%s:%d.%d,%d.%d %d %d\n", name,
					blocks[i].Line0, blocks[i].Col0,
					blocks[i].Line1, blocks[i].Col1,
					stmts,

  private static final long SMALL_TIMEOUT_MILLIS = 10;

  /** How long to wait when determining that a thread is blocked if we expect it to be blocked. */
  private static final long EXPECTED_HANG_DELAY_MILLIS = 75;

  /**
   * How long to wait when determining that a thread is blocked if we DON'T expect it to be blocked.
   */
  private static final long UNEXPECTED_HANG_DELAY_MILLIS = 10000;

  /**

		f.Blocks = f.Blocks[:n]
	}
}

// emptyBlock reports whether the block does not contain actual
// instructions.
func emptyBlock(b *Block) bool {
	for _, v := range b.Values {
		if v.Op != OpPhi {
			return false
		}
	}
	return true
}

// trimmableBlock reports whether the block can be trimmed from the CFG,
// subject to the following criteria:
//   - it should not be the first block.

Returning any error will also cancel the stream remotely.

CAREFUL: When utilizing two-way communication, it is important to ensure that the remote handler is not blocked on a send.
If the remote handler is blocked on a send, and the client is trying to send without the remote receiving, 
the operation would become deadlocked if the channels are full.

### Typed handlers

		if next == nil {
			break // No more waiters blocked.
		}

		w := next.Value.(waiter)
		if s.size-s.cur < w.n {
			// Not enough tokens for the next waiter.  We could keep going (to try to
			// find a waiter with a smaller request), but under load that could cause
			// starvation for large requests; instead, we leave all remaining waiters
			// blocked.
			//

        } else {
            this.mirroredRepositories = Collections.emptyList();
        }
    }

    public boolean isBlocked() {
        return blocked;
    }

    public void setBlocked(boolean blocked) {
        this.blocked = blocked;
    }

	// a bit baroque to remove a signal stack here only to add one
	// in minit, but it's a simple change that keeps NetBSD
	// working like other OS's. At this point all signals are
	// blocked, so there is no race.
	memset(&ss, 0, sizeof ss);
	ss.ss_flags = SS_DISABLE;
	sigaltstack(&ss, nil);

	crosscall1(ts.fn, setg_gcc, ts.g);
	return nil;

// Write writes data to writers.
func (p *multiWriter) Write(ctx context.Context, blocks [][]byte) error {
	for i := range p.writers {
		if p.errs[i] != nil {
			continue
		}
		if p.writers[i] == nil {
			p.errs[i] = errDiskNotFound
			continue
		}
		var n int
		n, p.errs[i] = p.writers[i].Write(blocks[i])
		if p.errs[i] == nil {
			if n != len(blocks[i]) {
				p.errs[i] = io.ErrShortWrite
				p.writers[i] = nil
			}