goroutine

consider this function : func doAllWork() error { var wg sync.WaitGroup wg.Add(3) for i := 0; i < 2; i++ { go func() { defer wg.Done() for j := 0; j < 10; j++ { result, err := work(j) if err != nil { // can't use `return err` here // what sould I put instead ? os.Exit(0) } } }() } wg.Wait() return nil } In each goroutine, the function work() is called 10 times. If one call to work() returns an error in any of the running goroutines, I want all the goroutines to stop immediately, and the program to exit. Is it ok to use os.Exit() here ? How should I handle this ? Edit : this question is

I have a slice that contains work to be done, and a slice that will contain the results when everything is done. The following is a sketch of my general process: var results = make([]Result, len(jobs)) wg := sync.WaitGroup{} for i, job := range jobs { wg.Add(1) go func(i int, j job) { defer wg.Done() var r Result = doWork(j) results[i] = r }(i, job) } wg.Wait() // Use results It seems to work, but I have not tested it thoroughly and am not sure if it is safe to do. Generally I would not feel good letting multiple goroutines write to anything , but in this case, each goroutine is limited to its

http://play.golang.org/p/vhaKi5uVmm package main import "fmt" var battle = make(chan string) func warrior(name string, done chan struct{}) { select { case opponent := <-battle: fmt.Printf("%s beat %s\n", name, opponent) case battle <- name: // I lost :-( } done <- struct{}{} } func main() { done := make(chan struct{}) langs := []string{"Go", "C", "C++", "Java", "Perl", "Python"} for _, l := range langs { go warrior(l, done) } for _ = range langs { <-done } } [1st Question] done <- struct{}{} How and Why do we need this weird-looking struct? Is it empty struct or anonymous struct? I googled it

Have loook at this contrived example: package main import "fmt" func printElo() { fmt.Printf("Elo\n") } func printHello() { fmt.Printf("Hello\n") } func main() { fmt.Printf("This will print.") i := 0 for i < 10 { go printElo() go printHello() i++ } } The output of this program would be just "This will print". Output of goroutines printElo() and printHello will not be emitted because, I guess, the main() function thread will finish before the goroutines have a chance to even start executing. What is the idiomatic way to make similar code work in Golang and not terminate prematurely? Simplest,

TL;TR: Please just go to the last part and tell me how you would solve this problem. I've begun using Golang this morning coming from Python. I want to call a closed-source executable from Go several times, with a bit of concurrency, with different command line arguments. My resulting code is working just well but I'd like to get your input in order to improve it. Since I'm at an early learning stage, I'll also explain my workflow. For the sake of simplicity, assume here that this "external closed-source program" is zenity , a Linux command line tool that can display graphical message boxes