Non blocking channel operations

Context

A select with a default case allows non‑blocking sends and receives. If no channel operation is ready, the default case executes immediately.

Example

Try to receive from a channel without blocking.

Code example

package main

import "fmt"

func main() {
    ch := make(chan string)

    select {
    case msg := <-ch:
        fmt.Println("received", msg)
    default:
        fmt.Println("no message received")
    }

    // Non‑blocking send
    select {
    case ch <- "hello":
        fmt.Println("sent")
    default:
        fmt.Println("send would block")
    }
}

Output

no message received
send would block

Useful links

• Go by Example: Non-Blocking Channel Operations
• Select with default