// whether to replicate as the target could be temporarily down
		opts.TargetArn = tgtArn
		replicate := cfg.Replicate(opts)
		var synchronous bool
		if tgt != nil {
			synchronous = tgt.replicateSync
		}
		dsc.Set(newReplicateTargetDecision(tgtArn, replicate, synchronous))
	}
	return dsc
}

// Standard headers that needs to be extracted from User metadata.
var standardHeaders = []string{

  ) {
    // Do nothing.
  }

  override fun noNewExchanges() {
    // Do nothing.
  }

  override fun cancel() {
    canceled = true
    // Close the raw socket so we don't end up doing synchronous I/O.
    rawSocket?.closeQuietly()
  }

  override fun retry(): RoutePlanner.Plan {
    return ConnectPlan(
      taskRunner = taskRunner,
      connectionPool = connectionPool,

      encodings[ 0x13] = encoding // Device Control 3 (oft. XOFF)
      encodings[ 0x14] = encoding // Device Control 4
      encodings[ 0x15] = encoding // Negative Acknowledgment
      encodings[ 0x16] = encoding // Synchronous idle
      encodings[ 0x17] = encoding // End of Transmission Block
      encodings[ 0x18] = encoding // Cancel
      encodings[ 0x19] = encoding // End of Medium
      encodings[ 0x1a] = encoding // Substitute

and the [go command documentation](/cmd/go#hdr-Build_and_test_caching).

### Go 1.23

Go 1.23 changed the channels created by package time to be unbuffered
(synchronous), which makes correct use of the [`Timer.Stop`](/pkg/time/#Timer.Stop)
and [`Timer.Reset`](/pkg/time/#Timer.Reset) method results much easier.
The [`asynctimerchan` setting](/pkg/time/#NewTimer) disables this change.

import okio.buffer
import okio.sink
import okio.source

/**
 * A socket connection to a remote peer. A connection hosts streams which can send and receive
 * data.
 *
 * Many methods in this API are **synchronous:** the call is completed before the method returns.
 * This is typical for Java but atypical for HTTP/2. This is motivated by exception transparency:

      override fun cancel() {
        exchange.cancel()
      }
    }
  }

  override fun route(): Route = route

  override fun cancel() {
    // Close the raw socket so we don't end up doing synchronous I/O.
    rawSocket?.closeQuietly()
  }

  override fun socket(): Socket = socket!!

  /** Returns true if this connection is ready to host new streams. */

   * CacheLoader#reload}.
   *
   * <p>As the default implementation of {@link CacheLoader#reload} is synchronous, it is
   * recommended that users of this method override {@link CacheLoader#reload} with an asynchronous
   * implementation; otherwise refreshes will be performed during unrelated cache read and write
   * operations.
   *

  }

  @Test
  fun networkInterceptorThrowsRuntimeExceptionSynchronous() {
    interceptorThrowsRuntimeExceptionSynchronous(true)
  }

  /**
   * When an interceptor throws an unexpected exception, synchronous callers can catch it and deal
   * with it.
   */
  private fun interceptorThrowsRuntimeExceptionSynchronous(network: Boolean) {
    addInterceptor(network) { chain: Interceptor.Chain? -> throw RuntimeException("boom!") }

It has an interesting, uncommon feature: using the same framework, it's possible to create APIs and also CLIs.

As it is based on the previous standard for synchronous Python web frameworks (WSGI), it can't handle Websockets and other things, although it still has high performance too.

!!! info

    }

    /**
     * Returns the final value of the associated {@link ClosingFuture}, or throws an exception as
     * {@link Future#get()} would.
     *
     * <p>Because the asynchronous operation has already completed, this method is synchronous and
     * returns immediately.
     *
     * @throws CancellationException if the computation was cancelled
     * @throws ExecutionException if the computation threw an exception