Waiting for some time until a condition is met

Question

5.00/5 (1 vote)

See more:

I have a code like this which executes in a different thread than main thread.

C#

if(_isSTminStarted && (_stMinExpired == false))
            {
                //wait till stMin is expired
                String message = string.Empty;
                do
                {
                    message = "Waiting till STmin expires " + DateTime.Now.ToString("h:mm:ss.fff");
                    _logger.Info(message);
                    

                } while (_stMinExpired == false);               
           
                _isSTminStarted = true;
                _timer.STminTimerStarted(_stMinRecieved);

                CanFrame consecutiveFrame = _fragmentedFrameQueue.Dequeue();
                PublishFrame(consecutiveFrame);
            }

Please see the do while loop , i have added that because i have to wait until a timer expires and _stMinExpired is set to true. Then only i should send next frame.

This flag is set when a System.threading.timer expires. But i don't think this is the ideal way to wait till that time. can you suggest some ways in which i can wait in this thread till that flag is set rather than putting do while loop.

Posted 10-Aug-11 22:27pm

glued-to-code

Updated 12-May-17 7:39am

Add a Solution

Comments

walterhevedeich 11-Aug-11 4:35am

I don't see any problem doing this, unless you don't want to log the message multiple times until _stMinExpired has been set to true.

3 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Firo Atrum Ventus · Accepted Answer · 2011-08-10T22:54:00

Solution 2

Try using AutoResetEvent[^].

Posted 10-Aug-11 22:54pm

Firo Atrum Ventus

Comments

glued-to-code 11-Aug-11 5:14am

Yes this seems good, i can give it a try.

BobJanova 11-Aug-11 5:39am

Correct approach, 5.

glued-to-code 11-Aug-11 5:48am

Hi, Thanks Bob and Firo... This was exactly what i wanted and i have used it and is working as i expected. Thanks again.

BobJanova · Accepted Answer · 2011-08-10T23:45:00

As Firo mentions, you want to use one of the event based wait handlers (AutoResetEvent or ManualResetEvent) for this. They are designed for exactly what you ask here: waiting until something happens in another thread at an unknown time.

class Test {
  AutoResetEvent waitHandle = new AutoResetEvent(false);

 void SpawnThread(){
  Thread t = new Thread(ThreadMethod);
  t.Start();
 }
 
 void ThreadMethod(){
  waitHandle.WaitOne();
  CanFrame consecutiveFrame = _fragmentedFrameQueue.Dequeue();
  PublishFrame(consecutiveFrame);
 }

 void SomeLongOtherMethod(){
  DoStuffThatTakesAWhile();
  waitHandle.Set(); // This will release the thread.
 }
}

You should never wait by using a tight loop. That will run a core at 100% CPU and make your app unpopular. Wait handles, and Thread.Sleep as well, are OS level triggers and put your thread into a non-running state that doesn't use CPU time.

OriginalGriff · Accepted Answer · 2011-08-10T22:33:00

Solution 1

Use Thread.Sleep[^] instead - it can wait for a specific time before your task does anything else.

Posted 10-Aug-11 22:33pm

OriginalGriff

Comments

glued-to-code 11-Aug-11 4:37am

But i don't have specific time until which i should put sleep. When the timer expires , i have to proceed further in the code. So in that case i can't put a sleep for specific time because a case can come where i neednot wait if timer has already expired.

OriginalGriff 11-Aug-11 5:08am

So instead sleep for 100ms, and check again, or kill your task and re-start it when the timer expires.

BobJanova 11-Aug-11 5:40am

This would work, but reset events are better if they can be used instead.

glued-to-code 11-Aug-11 5:49am

Thanks to both of you. i think Bob is right.

Waiting for some time until a condition is met

3 solutions

Solution 2

Solution 3

Solution 1

Add your solution here

Preview 0

Existing Members

...or Join us