[random] How to properly seed random number generator

just to toss it out for posterity: it can sometimes be preferable to generate a random string using an initial character set string. This is useful if the string is supposed to be entered manually by a human; excluding 0, O, 1, and l can help reduce user error.

var alpha = "abcdefghijkmnpqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ23456789"

// generates a random string of fixed size
func srand(size int) string {
    buf := make([]byte, size)
    for i := 0; i < size; i++ {
        buf[i] = alpha[rand.Intn(len(alpha))]
    }
    return string(buf)
}

and I typically set the seed inside of an init() block. They're documented here: http://golang.org/doc/effective_go.html#init