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5063 :: Async socket to server connection error handling

• adokitkat (orginal) [2019-08-02T01:14:46+02:00] view original

  Hello guys.

  Is there any way to find out if async socket proc connect() has established a connection or not - it just returns Future[void] either way - or a proper way to handle refused connections?

  My program crashes when I call

   await socket.recvLine() 
  Run

  for a socket where

   asyncCheck socket.connect(serverAddress, port.Port) 
  Run

  did not established a connection i.e. random IP, but it works ok when I connect to my server which listens.

  I've tried to catch an Exception and OSError (shown in traceback) but it didn't work. Shown errors:

  
  Error: unhandled exception: A request to send or receive data was disallowed because the socket is not connected and (when sending on a datagram socket using a sendto call) no address was supplied.
  
  Exception message: A request to send or receive data was disallowed because the socket is not connected and (when sending on a datagram socket using a sendto call) no address was supplied.
  
  Exception type: [OSError]
  Run

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• dom96 (orginal) [2019-08-02T10:17:02+02:00] view original

  Yes, connect raises when it cannot connect. I'm guessing you've been using asyncCheck and trying to catch the exception by wrapping try around that... you need to use await.

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• qqtop (orginal) [2019-08-02T16:29:58+02:00] view original

  But await works only inside an async proc

  were as asyncCheck can be used like this:

  
  
  when isMainModule :
     asyncCheck mastercon()
     runForever()
  Run

  How can we do:

  
  when isMainModule :
    await mastercon()
    runForever()
  Run

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• treeform (orginal) [2019-08-02T19:32:58+02:00] view original

  You need to use waitFor instead of await if you want to run {.async.} proc in non {.async.} context.

  
  when isMainModule :
    waitFor mastercon()
  Run

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• adokitkat (orginal) [2019-08-02T21:41:46+02:00] view original

  Thanks for replies! How about timeout for async connect? What's the correct way to do it?

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