I want to test wait4 function, but I'm not really familiar with child processes and so on, but I need to keep it working and during this time send it some signal and see reaction. Can you give me a little example of using wait4 in Go?
wait4 is deprecated on Linux, the proper way is to use exec.Command and call .Wait().
An example with signals:
func bgProcess(app string) (chan error, *os.Process, error) {
cmd := exec.Command(app)
ch := make(chan error, 1)
if err := cmd.Start(); err != nil {
return nil, nil, err
}
go func() {
ch <- cmd.Wait()
}()
return ch, cmd.Process, nil
}
func main() {
ch, proc, err := bgProcess("/usr/bin/cat")
if err != nil {
log.Fatal(err)
}
log.Println("Signal(os.Kill):", proc.Signal(os.Kill))
log.Println("cat returned:", <-ch)
}