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Windowing
environments
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ä |
Call
back system
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ä |
Runtime
environment catches events
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ä |
Mouse
clicks
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ä |
Interprocess
messages
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User
defined events
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Application
programs
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Define/register
events with the runtime
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ä |
Associate
each event with a user written
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subprogram
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When
an event occurs the runtime
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ä |
Causes
the corresponding subprogram to
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execute
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ä |
Subprogram
may cause other events....then
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returns
control to the runtime system
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ä |
Runtime
may or may not be multi-threaded
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If
it is it could associate each of the subprograms
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with a
new thread
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