Class: Thread::Mutex
Relationships & Source Files | |
Inherits: | Object |
Defined in: | thread_sync.c |
Overview
Mutex
implements a simple semaphore that can be used to coordinate access to shared data from multiple concurrent threads.
Example:
require 'thread'
semaphore = Mutex.new
a = Thread.new {
semaphore.synchronize {
# access shared resource
}
}
b = Thread.new {
semaphore.synchronize {
# access shared resource
}
}
Class Method Summary
-
.new ⇒ Mutex
constructor
Creates a new
Mutex
.
Instance Attribute Summary
-
#locked? ⇒ Boolean
readonly
Returns
true
if this lock is currently held by some thread. -
#owned? ⇒ Boolean
readonly
Returns
true
if this lock is currently held by current thread.
Instance Method Summary
-
#lock ⇒ self
Attempts to grab the lock and waits if it isn't available.
-
#sleep(timeout = nil) ⇒ Numeric
Releases the lock and sleeps
timeout
seconds if it is given and non-nil or forever. -
#synchronize ⇒ result of the block
Obtains a lock, runs the block, and releases the lock when the block completes.
-
#try_lock ⇒ Boolean
Attempts to obtain the lock and returns immediately.
-
#unlock ⇒ self
Releases the lock.
Constructor Details
.new ⇒ Mutex
Creates a new Mutex
Instance Attribute Details
#locked? ⇒ Boolean
(readonly)
Returns true
if this lock is currently held by some thread.
#owned? ⇒ Boolean
(readonly)
Returns true
if this lock is currently held by current thread.
Instance Method Details
#lock ⇒ self
Attempts to grab the lock and waits if it isn't available. Raises ::ThreadError if mutex
was locked by the current thread.
#sleep(timeout = nil) ⇒ Numeric
Releases the lock and sleeps timeout
seconds if it is given and non-nil or forever. Raises ::ThreadError if mutex
wasn't locked by the current thread.
When the thread is next woken up, it will attempt to reacquire the lock.
Note that this method can wakeup without explicit Thread#wakeup call. For example, receiving signal and so on.
#synchronize ⇒ result
of
the
block
Obtains a lock, runs the block, and releases the lock when the block completes. See the example under Mutex
.
#try_lock ⇒ Boolean
Attempts to obtain the lock and returns immediately. Returns true
if the lock was granted.
#unlock ⇒ self
Releases the lock. Raises ::ThreadError if mutex
wasn't locked by the current thread.