Golang golang-getchar (snippet)

Go programming example 'golang-getchar'

golang-getchar

Golang beginners example: golang-getchar

package main

import (
    "fmt"
    "os"
    "os/exec"
)

func readStdin(out chan string, in chan bool) {
    //no buffering
    exec.Command("stty", "-f", "/dev/tty", "cbreak", "min", "1").Run()
    //no visible output
    exec.Command("stty", "-f", "/dev/tty", "-echo").Run()

    var b []byte = make([]byte, 1)
    for {
        select {
        case <-in:
            return
        default:
            os.Stdin.Read(b)
            fmt.Printf(">>> %v: ", b)
            out <- string(b)
        }
    }
}

func main() {
    defer func() {
        exec.Command("stty", "-f", "/dev/tty", "echo").Run()
    }()
    stdin := make(chan string, 1)
    kill := make(chan bool, 1)
    var count int = 0
    var input string

    fmt.Print("this program don't wait for a enter-key\nyou can now start typing\npress \"q\" to quit\n\n")

    go readStdin(stdin, kill)
    for {
        str := <-stdin

        if str == "q" {
            kill <- true
            close(stdin)
            break
        }

        fmt.Println(str)
        input += str
        count++

        if count%10 == 0 {
            fmt.Printf("\n\nyou typed %v keys, quit the demo by pressing \"q\"\n\n", count)
            if count == 600 {
                fmt.Printf("Don't waste your time! Do something meaningful!")
                break
            }
        }
    }
    fmt.Printf("\n\nyou typed %v keys before you quit the program\n", count)
    fmt.Println(input)
}

Useful links

• Learn Go: https://golangr.com
• Download Go: https://golang.org