Is the behavior of the select function in Go predictable or random?

The behavior of the select function in Go is partially predictable, but when multiple channels are ready for operation simultaneously, the channel selection occurs randomly. This is done to prevent deadlocks and ensure fair distribution.

If only one channel is ready, select will choose that one. If no channels are ready and there is no default, select blocks.

Example:

select {
case msg1 := <-chan1:
    fmt.Println("Received from chan1", msg1)
case msg2 := <-chan2:
    fmt.Println("Received from chan2", msg2)
default:
    fmt.Println("No channels ready")
}

If both channels are ready, the choice between them will be random.