Re: ENRP Server Hunt Timer

On Tuesday 02 November 2004 14:16, c s chandrashekaran-A14667 wrote:
> I agree with the upper limit and with the idea of continuing to try (I
> think at the upper limited value of the timer). However it may be simpler
> to keep retrying forever. The application or user, can decide after certain
> number of failures to use ASAP (like register; name resoution etc) whether
> or not to shutdown. We would not need an additional configuration parameter
> in that case.

This would imply an asynchronous API, e.g. the user calls 
StartNameResolution(), which initiates the name resolution in background and 
returns immediately. Finally, the user application is notified - by signal (a 
bad idea!) or callback - and then calls a function GetNameResolutionResult() 
- or the user aborts the name resolution when he decides to have waited long 
enough. Example:

void callback()
{
   Notify main program that name resolution has been successful
}

ok = StartNameResolution();
if(!ok) {
   cerr << "ERROR: Unable to initiate name resolution" << endl;
   exit(1);
}
Start a timer -> nameResolutionCallback
...
while(...) {
   if(Name Resolution Event) {
      Name resolution successful!
   }
   if(Timer Event) {
      Name resolution failed!
   }
   ...
}

Probably, the program also has to care for thread safety in the callback 
function!


An asynchronous API is quite complicated. Giving a maximum number of trials 
directly to a NameResolution() function is much easier to use and much nearer 
to the existing DNS name resolution API. Example:

result = NameResolution("MyPoolHandle", 10 Trials)
if(result == NULL) {
   cerr << "ERROR: Name resolution failed!" << endl;
   exit(1);
}


Best regards
-- 
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 Dipl.-Inform. Thomas Dreibholz

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