When two or more goroutines have unsynchronized access to a shared resource and attempt to read and write to that resource at the same time, you have what’s called a race condition.

    example program that contains a race condition

    1. var (
    2.     counter int
    3.     wg sync.WaitGroup
    4. )
    7. func main() {
    8.     wg.Add(2)
    10.     go incCounter(1)
    11.     go incCounter(2)
    13.     wg.Wait()
    14.     fmt.Println("Final Counter:", counter)
    15. }
    17. func incCounter(id int) {
    18.     defer wg.Done()
    20.     for count := 0; count < 2; count++ {
    21.         value := counter
    22.         runtime.Gosched()
    23.         value++
    24.         counter = value
    25.     }
    26. }

    Build the code using the race detector flag
    go build -race