Class: Concurrent::Semaphore
- Inherits:
-
SemaphoreImplementation
- Object
- Concurrent::Semaphore
- Defined in:
- lib/concurrent-ruby/concurrent/atomic/semaphore.rb
Overview
A counting semaphore. Conceptually, a semaphore maintains a set of permits. Each #acquire blocks if necessary until a permit is available, and then takes it. Each #release adds a permit, potentially releasing a blocking acquirer. However, no actual permit objects are used; the Semaphore just keeps a count of the number available and acts accordingly. Alternatively, permits may be acquired within a block, and automatically released after the block finishes executing.
Instance Method Summary collapse
-
#acquire(permits = 1) ⇒ nil, BasicObject
Acquires the given number of permits from this semaphore, blocking until all are available.
-
#available_permits ⇒ Integer
Returns the current number of permits available in this semaphore.
-
#drain_permits ⇒ Integer
Acquires and returns all permits that are immediately available.
-
#initialize(count) ⇒ Object
constructor
Create a new ‘Semaphore` with the initial `count`.
-
#release(permits = 1) ⇒ nil
Releases the given number of permits, returning them to the semaphore.
-
#try_acquire(permits = 1, timeout = nil) ⇒ true, ...
Acquires the given number of permits from this semaphore, only if all are available at the time of invocation or within ‘timeout` interval.
Constructor Details
#initialize(count) ⇒ Object
Create a new ‘Semaphore` with the initial `count`.
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# File 'lib/concurrent-ruby/concurrent/atomic/semaphore.rb', line 164 class Semaphore < SemaphoreImplementation end |
Instance Method Details
#acquire(permits = 1) ⇒ nil, BasicObject
Acquires the given number of permits from this semaphore,
blocking until all are available. If a block is given,
yields to it and releases the permits afterwards.
is given, its return value is returned.
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# File 'lib/concurrent-ruby/concurrent/atomic/semaphore.rb', line 164 class Semaphore < SemaphoreImplementation end |
#available_permits ⇒ Integer
Returns the current number of permits available in this semaphore.
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# File 'lib/concurrent-ruby/concurrent/atomic/semaphore.rb', line 164 class Semaphore < SemaphoreImplementation end |
#drain_permits ⇒ Integer
Acquires and returns all permits that are immediately available.
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# File 'lib/concurrent-ruby/concurrent/atomic/semaphore.rb', line 164 class Semaphore < SemaphoreImplementation end |
#release(permits = 1) ⇒ nil
Releases the given number of permits, returning them to the semaphore.
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# File 'lib/concurrent-ruby/concurrent/atomic/semaphore.rb', line 164 class Semaphore < SemaphoreImplementation end |
#try_acquire(permits = 1, timeout = nil) ⇒ true, ...
Acquires the given number of permits from this semaphore,
only if all are available at the time of invocation or within
`timeout` interval. If a block is given, yields to it if the permits
were successfully acquired, and releases them afterward, returning the
block's return value.
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# File 'lib/concurrent-ruby/concurrent/atomic/semaphore.rb', line 164 class Semaphore < SemaphoreImplementation end |