I have a question about C#. How can I stop asynchronous read/write operation
( BeginReceive() / BeginSend() ) if timeout occurs?
The Socket class doesn't make any cancel method available.
I used CancelIo(HANDLE hFile) method (declared in Winbase.h) in C++.
Thanks for help.
Olek 5 5646
You could always spawn a new thread which then calls the synchronous
version, into which you can place a timeout parameter.
"a.kostrzew a" <aX.kostrzewaX@ remove_this_and _X.uposX.comX.p lX> wrote in
message news:bm******** **@nemesis.news .tpi.pl...
I have a question about C#. How can I stop asynchronous read/write operation
( BeginReceive() / BeginSend() ) if timeout occurs?
The Socket class doesn't make any cancel method available.
I used CancelIo(HANDLE hFile) method (declared in Winbase.h) in C++.
Thanks for help.
Olek
I might be wrong here.. but, can you call EndSend() to complete the
operation?
--
Girish Bharadwaj
"Daniel Bass" <I'm really @ sick of spam> wrote in message
news:O8******** ******@TK2MSFTN GP10.phx.gbl... You could always spawn a new thread which then calls the synchronous version, into which you can place a timeout parameter.
"a.kostrzew a" <aX.kostrzewaX@ remove_this_and _X.uposX.comX.p lX> wrote in message news:bm******** **@nemesis.news .tpi.pl... I have a question about C#. How can I stop asynchronous read/write
operation ( BeginReceive() / BeginSend() ) if timeout occurs? The Socket class doesn't make any cancel method available. I used CancelIo(HANDLE hFile) method (declared in Winbase.h) in C++.
Thanks for help. Olek
Yes, of course.
I call asynchronous read operation in this way:
IAsyncResult oResult = oSocket.BeginRe ceive(...);
oWH = m_oResult .AsyncWaitHandl e;
// oEventsHandler - my class object
oEventsHandler. WaitForGroupEQ( Timeout.Infinit e ,nGroupId,out nEvent);
int nNumberOfBytesR ead = ReadEnd();
But I can't break this operation.
Best regards,
Olek
Użytkownik "Girish Bharadwaj" <girishb.at.mvp s.dot.org> napisał w wiadomo¶ci
news:OM******** ******@TK2MSFTN GP09.phx.gbl... I might be wrong here.. but, can you call EndSend() to complete the operation?
-- Girish Bharadwaj "Daniel Bass" <I'm really @ sick of spam> wrote in message news:O8******** ******@TK2MSFTN GP10.phx.gbl... You could always spawn a new thread which then calls the synchronous version, into which you can place a timeout parameter.
"a.kostrzew a" <aX.kostrzewaX@ remove_this_and _X.uposX.comX.p lX> wrote in message news:bm******** **@nemesis.news .tpi.pl... I have a question about C#. How can I stop asynchronous read/write operation ( BeginReceive() / BeginSend() ) if timeout occurs? The Socket class doesn't make any cancel method available. I used CancelIo(HANDLE hFile) method (declared in Winbase.h) in C++.
Thanks for help. Olek
"a.kostrzew a" <aX.kostrzewaX@ remove_this_and _X.uposX.comX.p lX> wrote in message news:<bm******* ***@atlantis.ne ws.tpi.pl>... Yes, of course. I call asynchronous read operation in this way:
IAsyncResult oResult = oSocket.BeginRe ceive(...); oWH = m_oResult .AsyncWaitHandl e; // oEventsHandler - my class object oEventsHandler. WaitForGroupEQ( Timeout.Infinit e ,nGroupId,out nEvent); int nNumberOfBytesR ead = ReadEnd();
But I can't break this operation.
Olek -
From what I can tell from your code it looks like you are blocking
the main thread until the EndReceive() callback method fires. This
somewhat defeats the purpose of using an asynchronous socket call.
Instead of waiting indefinitely for an answer, why don't you put a
reasonable timeout time in the WaitForGroupEQ method. When the timeout
is reached you know there wasn't a response. If you then Close() the
Socket object, the EndReceive() method will fire, and throw an
Exception. You should catch the Exception in a try-catch block and
handle it accordingly.
Alternatively, you can use the blocking Receive() method, and set
the ReceiveTimeout Socket option property to a reasonable value. The
Receive() method will throw an Exception if the timeout is reached
before data is received. Hope this helps solve your problem.
Rich Blum - Author
"C# Network Programming" (Sybex) http://www.sybex.com/sybexbooks.nsf/Booklist/4176
"Network Performance Open Source Toolkit" (Wiley) http://www.wiley.com/WileyCDA/WileyT...471433012.html
I'm grateful for help.
But in Yours solution I can't send any message after timeout on receive
(socket is closed!).
This way I would like to avoid Close() method.
Unfortunely I can't use alternatively method - blocking Receive().
Olek
Uzytkownik "Rich Blum" <ri*******@juno .com> napisal w wiadomosci
news:cc******** *************** ***@posting.goo gle.com... "a.kostrzew a" <aX.kostrzewaX@ remove_this_and _X.uposX.comX.p lX> wrote in
message news:<bm******* ***@atlantis.ne ws.tpi.pl>... Yes, of course. I call asynchronous read operation in this way:
IAsyncResult oResult = oSocket.BeginRe ceive(...); oWH = m_oResult .AsyncWaitHandl e; // oEventsHandler - my class object oEventsHandler. WaitForGroupEQ( Timeout.Infinit e ,nGroupId,out nEvent); int nNumberOfBytesR ead = ReadEnd();
But I can't break this operation. Olek -
From what I can tell from your code it looks like you are blocking the main thread until the EndReceive() callback method fires. This somewhat defeats the purpose of using an asynchronous socket call. Instead of waiting indefinitely for an answer, why don't you put a reasonable timeout time in the WaitForGroupEQ method. When the timeout is reached you know there wasn't a response. If you then Close() the Socket object, the EndReceive() method will fire, and throw an Exception. You should catch the Exception in a try-catch block and handle it accordingly.
Alternatively, you can use the blocking Receive() method, and set the ReceiveTimeout Socket option property to a reasonable value. The Receive() method will throw an Exception if the timeout is reached before data is received. Hope this helps solve your problem.
Rich Blum - Author "C# Network Programming" (Sybex) http://www.sybex.com/sybexbooks.nsf/Booklist/4176 "Network Performance Open Source Toolkit" (Wiley) http://www.wiley.com/WileyCDA/WileyT...471433012.html This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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