Atomic Operations

Hi there:

Does anyone know if there is possibility of doing Atomic Operations in
C++?
****** NEW Lines:
Particularly I am interested to have the solution on Windows NT Platform.
Example:
I want to COMMIT to a database (operation 1) and rename a file (operation 2) in one operation. Operation 2 is to be done after Operation 1 but I don't want to do Operation 1 without making sure that Operation 2 is also done!!

By Atomic I mean a block of code that either gets executed entirely
without interruption by the CPU or it does not get executed at all.

I might be wrong but I think Synchronize keyword in Java does that.
farshidAsked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

md041797Commented:
On what platform?
There are no C++ language constructs, so you need to know the operating system.
0
byangCommented:
Exactly what do you need to do ?
0
heaveyrlCommented:
In MS Visual C++ (4.2CAB) use help/query type in the keyword
"synchronization" then read all the text up on "Application and Thread Support Classes" and "MultiThreading: How to Use Synchronization Classes".

At the kernel is Mutex, which you'll have to create, manage and observe to give your go / no go functionality.


0
farshidAuthor Commented:
Edited text of question
0
aviadCommented:
There are two ways to handle pieces of code that need to be protected through mutual exclusion from other pieces of code.
1. Mutex Semaphores
2. Using "Critical Sections"

From your question I think the latter is more suitable for you. And there are two ways to use critical sections in windows NT.
1. By using the functions InitializeCriticalSection(), EnterCriticalSection(), LeaveCriticalSection()
2. By using the CCriticalSection and the CSingleLock or CMultiLock classes.

The first method is simple and straightforward, you initialize a so-called "critical-section" object somewhere in the initialization of your program, this object has no meaning in itself, but will be used in subsequent calls to EnterCriticalSection() and LeaveCriticalSection().

The second method is a bit more complicated but is more object-oriented. Using the second method, the class containing the critical section should include a data member of type CCriticalSection. Then in order to handle the controlled section, you should define a local variable of type CSingleLock (or CMultiLock if you want to wait on more than one CCriticalSection object). An example will show it best:

Assume class "List" has critical sections of code dealing with insertions and removals of items:

class List {
private:
    CCriticalSection Sync;
public:
    void Add() {
        CSingleLock SLock(&Sync);
        SLock.Lock();

              //{ critical section code }

        SLock.Unlock()
    }
...
};

Hope this helps.
Aviad.
0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
C++

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.