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n |
Semaphores
provide a powerful tool for
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|
enforcing
mutual exclusion and coordinate
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|
processes
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n |
But wait(S)
and signal(S) are scattered
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among several
processes. Hence, difficult
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|
to understand
their effects
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n |
Usage must be
correct in all the processes
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n |
One bad (or
malicious) process can fail the
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entire
collection of processes
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