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Thread synchronizing

Posted on 2004-04-29
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Last Modified: 2010-04-05
This is a 'It works but I guess it can be done more clever' question:
A thread has to wait until a second thread has done its work. Actually I use a critical section:

Thread 1:
procedure TriggerSecondThreadAndWait;
begin
  TriggerThread_2;
  EnterSection;   // Suspend thread 1, I'm sure thread 2 already entered the section
  LeaveSection;
end;

Thread 2:
procedure DoWork;
begin
  EnterSection;   // To suspend thread 1
  DoSomeWork;
  LeaveSection;   // Resume thread 1
end;

Can I use a 'WaitForXYZ' instead. I've never done this before...
Thank you!
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Question by:__alex
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4 Comments
 
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Expert Comment

by:sftweng
ID: 10947352
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LVL 2

Author Comment

by:__alex
ID: 10947625
???
TThread.WaitFor waits for termination of the thread. I don't want to terminate it.
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Accepted Solution

by:
sftweng earned 250 total points
ID: 10947699
Are you looking to use TEvent.WaitFor then?

Waits until another thread or process turns on the signal of the event object.

type TWaitResult = (wrSignaled, wrTimeout, wrAbandoned, wrError);
function WaitFor(Timeout: DWORD): TWaitResult;

Description

Call WaitFor to wait until the signal of the event object is turned on. If the signal is not set after TimeOut milliseconds, WaitFor returns anyway. WaitFor returns one of the following values:

Value      Meaning

wrSignaled      The signal of the event object was set.
wrTimeOut      The time specified by the TimeOut parameter elapsed without the signal being set.
wrAbandoned      The event object was destroyed before the TimeOut period elapsed.
wrError      An error occurred while waiting. Check the LastError property for an error code giving more information.
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Author Comment

by:__alex
ID: 10947966
Yep, that's it, thank you!
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