The elapsed time, in milliseconds, required to invert the caret is called the blink time. The caret will blink as long as the thread that owns the message queue has a message pump processing the messages.
The user can set the blink time of the caret using the Control Panel and applications should respect the settings that the user has chosen. An application can determine the caret's blink time by using the GetCaretBlinkTime function. If you are writing an application that allows the user to adjust the blink time, such as a Control Panel applet, use the SetCaretBlinkTime function to set the rate of the blink time to a specified number of milliseconds.
The flash time is the elapsed time, in milliseconds, required to display, invert, and restore the caret's display. The flash time of a caret is twice as much as the blink time.