In: |
thread.rb
|
Parent: | Object |
ConditionVariable objects augment class Mutex. Using condition variables, it is possible to suspend while in the middle of a critical section until a resource becomes available (see the discussion on page 117).
Example:
require 'thread' mutex = Mutex.new resource = ConditionVariable.new a = Thread.new { mutex.synchronize { # Thread 'a' now needs the resource resource.wait(mutex) # 'a' can now have the resource } } b = Thread.new { mutex.synchronize { # Thread 'b' has finished using the resource resource.signal } }
Releases the lock held in mutex and waits; reacquires the lock on wakeup.
# File thread.rb, line 191 def wait(mutex) mutex.exclusive_unlock do @waiters.push(Thread.current) Thread.stop end mutex.lock end
Wakes up the first thread in line waiting for this lock.
# File thread.rb, line 202 def signal begin t = @waiters.shift t.run if t rescue ThreadError retry end end