Resignaling a Condition (original) (raw)
9 Conditions 9.1 Condition System Concepts
9.1.4 Signaling and Handling Conditions
9.1.4.1 Signaling
9.1.4.1.1 Resignaling a Condition
During the dynamic extent of the signaling process for a particular condition object, signaling the same condition object again is permitted if and only if the situation represented in both cases are the same.
For example, a handler might legitimately _signal_the condition object that is its _argument_in order to allow outer handlers first opportunity to _handlethe condition. (Such a handlers is sometimes called a "default handler.") This action is permitted because the situation which the second_signaling process is addressing is really the same situation.
On the other hand, in an implementation that implemented asynchronous keyboard events by interrupting the user process with a call to signal, it would not be permissible for two distinct asynchronous keyboard events to signal identical condition _objects_at the same time for different situations.