thread-safety

问题 I'm wondering if there is a boost equivalent of ManualResetEvent? Basically, I'd like a cross-platform implementation... Or, could someone help me mimic ManualResetEvent's functionality using Boost::thread? Thanks guys 回答1: It's pretty easy to write a manual reset event when you have mutexes and condition variables. What you will need is a field that represents whether your reset event is signalled or not. Access to the field will need to be guarded by a mutex - this includes both setting

问题 I know that I must call Synchronize to update the vcl from a thread that did not create the controls or send a message to the window. I have often heard the word not thread safe but I can't find an actual explanation about what is happening. I know the application might crash with an access violation, but again I don't know why? Please shed a light on this topic. 回答1: About GDI thread safety in Windows, see this reference article. It clearly states that you can access safely handles from

问题 I am looking at improving a package that I believe not to be threadsafe when its input is shared between multiple worker threads. According to TDD principles, I should write some tests that fail in the first instance, and these would certainly be useful in assessing the problem. I realise that this is not a simple thing to acheive, and that naively, multi-threaded tests will be nondeterministic as the operating system will determine scheduling and the exact order that various operations are

问题 This question already has an answer here : What's the difference in using ReentrentLock and Synchronized(object)? [duplicate] (1 answer) Closed 2 years ago . I have used the synchronized keyword and re-entrant locks in Java, but I don't understand how they differ, or which is appropriate for a given situation. How do I decide when should I use synchronized and when I should use re-entrant locks? 回答1: A ReentrantLock is: A reentrant mutual exclusion Lock with the same basic behavior and

问题 This question already has an answer here : What's the difference in using ReentrentLock and Synchronized(object)? [duplicate] (1 answer) Closed 2 years ago . I have used the synchronized keyword and re-entrant locks in Java, but I don't understand how they differ, or which is appropriate for a given situation. How do I decide when should I use synchronized and when I should use re-entrant locks? 回答1: A ReentrantLock is: A reentrant mutual exclusion Lock with the same basic behavior and

问题 I'm new to C++ and am writing a multi-threaded app whereby different writers will be pushing objects onto a stack and readers pulling them off the stack (or at least pushing the pointer to an object).. Are there any structures built-into C++ which can handle this without adding locking code etc.? If not, what about the Boost libraries? EDIT: Hi. Thanks for the initial great answers. I guess one reason I thought this could be built-in was that I was thinking purely in x86 space and thought

问题 I am Java newbie (and RoR developer). I have a simple program. Ball is shared amont players. Ball should be passed to random Player. Ok here goes the code: class Ball { private int currentPlayer; public void setCurrentPlayer( int currentPlayer, int fromWho ) { this.currentPlayer = currentPlayer; System.out.println( "Ball:setCurrentPlayer " + fromWho + " ---> " + currentPlayer ); } public int getCurrentPlayer() { return currentPlayer; } } class Player implements Runnable { private int myID;

问题 This question already has answers here : Thread-safe setting of a variable (Java)? (5 answers) Closed 3 years ago . Suppose I have two threads updating an object, and one thread reading from that object with no synchronization. Obviously, this is run condition. However, I am wondering if the variable itself can only partially written. public class CommonObject extends Object { static int memberVar=-1; } public class Input1Thread extends Thread { public void run() { while(true) CommonObject

问题 I have the following code: import threading def send_to_server(lst): #Some logic to send the list to the server. while 1: lst = [] for i in range(1000): lst.append(i) task = threading.Thread(target=send_to_server,args(copy(lst),)) task.start() I have a few Questions: 1) The idea for using threads is because sending to server takes time and I want to continue generating the data without any stop. The problem with this code is that if I created thread #3 and its taking long time to process, By

问题 I want to know how many active threads are there for a particular Thread class. Lets say I have a class T which extends thread. In some other class (Ex: Demo) , I want to get the thread count for the T class Thread. I do know Thread.activeCount() method but it will get the count for a thread group. It does not server my need here. Lets say I have T1 and T2 classes which extends thread and In the Demo class I want to get How many T2 active threads are there. How should I achieve this? Any