require 'thread'
mutex = Mutex.new
shared_resource = 0
for i in 0..10000
Thread.new do
mutex.synchronize { shared_resource += 1 }
end
Thread.new do
mutex.synchronize { shared_resource -= 1 }
end
end
puts shared_resource
我试着运行这个Ruby程序来测试互斥锁.synchronize并在每次运行时得到0，但每次我运行这个程序时它都会给我随机值.需要帮助解决这个问题，以获得0，并帮助我了解如何在Ruby中使用互斥锁和锁
您的问题不是互斥体，因为同步会在块执行期间锁定它.你的问题是当你达到puts shared_resource时，线程执行尚未完成.
为了解决这个问题，你需要通过调用Thread#join来确保所有线程都完成了，例如:
require 'thread'
mutex = Mutex.new
shared_resource = 0
threads = []
400.times do |i|
threads << Thread.new do
mutex.synchronize {shared_resource += 1}
end
threads << Thread.new do
mutex.synchronize {shared_resource -= 1}
end
end
puts shared_resource
#=> some number
# see how many threads are still running
puts threads.map(&:status)
threads.map(&:join)
puts shared_resource
#=> 0