I am refactoring some code and am wondering about the use of a 'lock' in the instance constructor. public class MyClass { private static Int32 counter = 0; private Int32 myCount; public MyClass() { lock(this) { counter++; myCount = counter; } } } Please confirm Inst...
I have a C# singleton class that multiple classes use. Is access through Instance to the Toggle() method thread-safe? If yes, by what assumptions, rules, etc. If no, why and how can I fix it? public class MyClass { private static readonly MyClass instance = new MyClass(); public static MyClass Instance { get { retur...
I was able to implement a thread-safe Dictionary in C# by deriving from IDictionary and defining a private SyncRoot object: public class SafeDictionary<TKey, TValue>: IDictionary<TKey, TValue> { private readonly object syncRoot = new object(); private Dictionary<TKey, TValue> d = new Dictionary<TKey, TValue>(); public objec...
I'm writing an app in C# (.net 3.5) and I have a question about class design: I'd like to create a class which accesses a file (read, write) and provides its content to the users (instanciators) of the class. The most common operation on an instance will be to retrieve a certain value from the file. The actual read and write (io) opera...
If I create classes, that are used at the moment only in a single thread, should I make them thread-safe, even if I don't need that at the moment? It could be happen, that I later use this class in multiple threads, and at that time I could get race conditions and may have a hard time to find them if I didn't made the class thread-safe i...
Edit: The code here still has some bugs in it, and it could do better in the performance department, but instead of trying to fix this, for the record I took the problem over to the Intel discussion groups and got lots of great feedback, and if all goes well a polished version of Atomic float will be included in a near future release ...
This function exists on OS X and allows you to pass custom local to the function. setlocale is not thread-safe, and passing locale as parameter is. If there is no equivalent, any way of locale-independent printf, or printf just for doubles (%g) will be ok. ...
When you lock an object is that object locked throughout the whole application? For Example, this snippet from C# 3.0 in a Nutshell Section 19.6.1 "Thread Safety and .NET Framework Types": static void AddItems( ) { for (int i = 0; i < 100; i++) lock (list) list.Add ("Item " + list.Count); string[] items; l...
I'm using IStorage's Compound File Implementation from C# (StgCreateDocfile). Is it safe to access one IStorage / IStream instance from multiple threads, provided I synchronized the reads and writes myself? Or are there any COM issues that might be problematic here? For example, can I safely call EnumElements to get all streams in the ...
In my Java program, I create a OtpNode and a "named" OtpMBox. Whenever a message is received via this mbox, some time-consuming operation needs to be performed after which a reply message is sent back. Since this operation is time-consuming, subsequent messages sent to the mbox won't be processed immediately. So I want to use Java thre...
Consider the "double-check idiom for lazy initialization of instance fields": // Item 71 in Effective Java copied from this interview with Bloch. private volatile FieldType field; FieldType getField() { FieldType result = field; if (result == null) { // First check (no locking) synchronized(this) { result = f...
Howdy, I have been bitten by a poorly architected solution. It is not thread safe! I have several shared classes and members in the solution, and during development all was cool... BizTalk has sunk my battle ship. We are using a custom BizTalk Adapter to call my assemblies. The Adapter is calling my code and running things in ...
I'm looking for articles, forum or blog posts dealing with SharePoint and thread safety? I'm quite sure there are some special aspects regarding thread safety that have to be considered when working with the SharePoint object model. Actually I didn't find many information about this, yet. So I'm looking forward to your answers. Bye...
Here is a simplified version of my application showing what I'm doing. /* in my app's main(): Runner run = new Runner(); run.dowork(); */ class Runner { private int totalWorkers = 2; private int workersDone = 0; public synchronized void workerDone() { workersDone++; notifyAll(); } public synchronized void dowork() { ...
What is the difference between the concepts of "Code Re-entrancy" and "Thread Safety"? As per the link mentioned below, a piece of code can be either of them, both of them or neither of them. Reentrant and Thread safe code I was not able to understand the explaination clearly. Help would be appreciated. ...
Hi all.. I've been thinking, just how deep into everything do you have to go before something is automatically thread-safe? Quick example: int dat = 0; void SetInt(int data) { dat = data; } .. Would this method be considered threadsafe? I ussually wrap all my set-methods in mutex'es, just to be sure, but everytime I do so I can'...
The two methods Suspend() and Resume() are obsolete in C# .Net 2.0. What are other alternatives and any examples? ...
I have a dialog in MFC with a CStatusBar. In a separate thread, I want to change the pane text of status bar. However MFC complains with asserts? How is it done? An example code would be great. ...
Is the .NET class System.Net.CookieContainer thread safe? --Update: Turnkey answered-- Is there any way to ensure thread safeness to variables which are modified during asynchronous requests (ie. HttpWebRequest.CookieContainer)? Is there any attribute to highlight thread safe classes? --Update: If thread-safeness is described on MSDN th...
I know that when creating a DLL and declaring items as "Shared" (Static in C#) that they are instantiated when first called, and then that object reference lives on as the single reference. So declaring a shared string property once set can be called again to retreive the same value. And that thread safety is then a Major concern withi...