go/src/runtime/retry.go

// retryOnEAGAIN retries a function until it does not return EAGAIN.
// It will use an increasing delay between calls, and retry up to 20 times.
// The function argument is expected to return an errno value,
// and retryOnEAGAIN will return any errno value other than EAGAIN.
// If all retries return EAGAIN, then retryOnEAGAIN will return EAGAIN.
func retryOnEAGAIN(fn func() int32) int32 { … }