Is it OK to leave a channel open?

Question

Is it OK to leave a Go channel open forever (never close the channel) if I never check for its state? Will it lead to memory leaks? Is the following code OK?

func (requestCh chan<- Request) GetResponse(data RequestData) Response {
    reply := make(chan Response)
    requestCh <- Request{data: data, replyCh: reply}
    return <-reply
}

Answer 1

It's OK to leave a Go channel open forever and never close it. When the channel is no longer used, it will be garbage collected.

Note that it is only necessary to close a channel if the receiver is looking for a close. Closing the channel is a control signal on the channel indicating that no more data follows.

Design Question: Channel Closing

Answer 2

Yes, it is ok to keep a channel open. As the go programming language book stated:

You needn't close every channel when you've finished with it. It's only necessary to close a channel when it is important to tell the receiving goroutines that all data have been sent. A channel that the garbage collector determinies to be unreachable will have its resources reclaimed whether or not it is closed. (Don't confuse this with the close operation for open files. It is important to call the Close method on every file when you've finished with it.)

Answer 3

Yes, it's OK to leave the channel open, and in fact it is typical. A channel being open does not constitute a reference to the channel object, and so does not keep it from being garbage collected.

Answer 4

Go is garbage collected, so you don't really have to 'free' anything.

There is possibility to close channels, but it's mostly used as - close(channel) - tell the goroutine (or main program) that nothing else will be sent on that channel.