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 handle
the 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.
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