Synchronous and Asynchronous Communication

Blocking of goroutines

By default, communication is synchronous, and unbuffered, which means the send operation does not complete until there is a receiver to accept the value. One can think of an unbuffered channel as if there is no space in the channel for data. There must be a receiver ready to receive data from the channel, and then the sender can hand it over directly to the receiver. So, channel send/receive operations block until the other side is ready:

• A send operation on a channel (and the goroutine or function that contains it) blocks until a receiver is available for the same channel ch. If there’s no recipient for the value on ch, no other value can be put in the channel, which means no new value can be sent in ch when the channel is not empty. So, the send operation will wait until ch becomes available again. This is the case when the

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