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The C Users' Group Library 1994 August
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wc-cdrom-cusersgrouplibrary-1994-08.iso
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vol_300
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310_02
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semaphor.st
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1990-04-20
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Class Semaphore :List
| excessSignals |
[ new
excessSignals <- 0
| new: aNumber
excessSignals <- aNumber
| signal
<StartAtomic>. "start atomic action"
(self isEmpty)
ifTrue: [excessSignals <- excessSignals + 1]
ifFalse: [self removeFirst unblock].
<EndAtomic> "end atomic action"
| wait
<StartAtomic>. "start atomic actions"
(excessSignals = 0)
ifTrue: [self addLast: selfProcess.
selfProcess block]
ifFalse: [excessSignals <- excessSignals - 1].
<EndAtomic> "end atomic actions"
]