Search results
Results from the WOW.Com Content Network
In computer science, a semaphore is a variable or abstract data type used to control access to a common resource by multiple threads and avoid critical section problems in a concurrent system such as a multitasking operating system. Semaphores are a type of synchronization primitive. A trivial semaphore is a plain variable that is changed (for ...
Quotation marks are to show that you are using the correct word as quoted from the original source. For example: His tombstone was inscribed with the name "Aaron" instead of the spelling he used during his life. Avoid using ALL CAPS and small caps for emphasis (for legitimate uses, see WP:Manual of Style/Capital letters § All caps).
Semaphore (lit. ' apparatus for signalling '; from Ancient Greek σῆμα (sêma) 'mark, sign, token' and Greek -φόρος (-phóros) 'bearer, carrier') [1] is the use of an apparatus to create a visual signal transmitted over distance. [2] [3] A semaphore can be performed with devices including: fire, lights, flags, sunlight, and moving arms.
The word telegraph (from Ancient Greek: τῆλε 'at a distance' and γράφειν 'to write') was coined by the French inventor of the semaphore telegraph, Claude Chappe, who also coined the word semaphore. [2] A telegraph is a device for transmitting and receiving messages over long distances, i.e., for telegraphy.
A US Navy crewman signals the letter 'U' using flag semaphore during an underway replenishment exercise (2005). Flag semaphore (from the Ancient Greek σῆμα (sêma) 'sign' and - φέρω (-phero) '-bearer' [1]) is a semaphore system conveying information at a distance by means of visual signals with hand-held flags, rods, disks, paddles, or occasionally bare or gloved hands.
The Chicago Manual of Style suggests the use of an ellipsis for any omitted word, phrase, line, or paragraph from within but not at the end of a quoted passage. There are two commonly used methods of using ellipses: one uses three dots for any omission, while the second one makes a distinction between omissions within a sentence (using three ...
The name "Semafor" is derived from the word "semaphore", which "appears in similar form in many languages". According to The New York Times , "semaphore" is "often used in a nautical context" and can be described as "a visual signaling apparatus often involving flags, lights and arm gestures". [ 5 ]
If the semaphore variable is now negative, the process executing wait() is blocked (i.e., added to the semaphore's queue) until the value is greater or equal to 1. Otherwise, the process continues execution, having used a unit of the resource. signal(): Increments the value of semaphore variable by 1.