semaphore
US /ˈsem.ə.fɔːr/
UK /ˈsem.ə.fɔːr/
1.
a system of sending messages by holding two flags in certain positions according to a code
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Sailors used semaphore to communicate between ships.
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The old lighthouse used a form of semaphore to warn ships of danger.
2.
(in computing) a variable or abstract data type used to control access to a common resource by multiple processes and avoid critical section problems in a concurrent system such as a multitasking operating system
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The operating system uses a semaphore to manage access to shared memory.
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Understanding semaphores is crucial for concurrent programming.
1.
send (a message) by semaphore
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They tried to semaphore a warning to the distant ship.
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Can you semaphore the message to the other side of the field?