What is the difference between using the WithTimeout function and WithDeadline in the context of execution time control?

The WithTimeout and WithDeadline functions in Go are used to create a context with a time limit, but they differ in how this limit is set:

• WithTimeout(parent, timeout) creates a context that is automatically canceled after the specified duration timeout from the current moment. That is, the timer starts when called.

• WithDeadline(parent, deadline) creates a context that is canceled at a specific point in time deadline (of type time.Time). This allows setting an exact time when the context will expire.

Example:

ctx1, cancel1 := context.WithTimeout(context.Background(), 5*time.Second)
// ctx1 will be canceled after 5 seconds from now

deadline := time.Now().Add(5 * time.Second)
ctx2, cancel2 := context.WithDeadline(context.Background(), deadline)
// ctx2 will be canceled exactly at the deadline time

Thus, WithTimeout is convenient when you need to specify a duration, while WithDeadline is useful when a specific point in time is important.