In the last days I was going to spent some time debugging the random NEd Nim
editor crashes. Unfortunately, while I got some crashes some weeks ago when
working on the chess game, I was not able to generate crashes when testing. So
I think I have to wait until a real crash occurs again, and then try to
remember how it was generated...
One problem persists. That is terminating NEd and launching it again
immediately. For this case the port is still in use, and communication with
nimsuggest does not work. After about two minutes port is destroyed by OS and
all works again.
That is a well known net communication problem of course, and not a big problem
in real life. One solution is of course just waiting 2 minutes (can be up to 4
minutes from socket specs.) Another solution may be not using a fixed port
number, but choosing one from a random range. But of course both is not nice.
So I spent two hours for googling yesterday -- I found many questions with
similar problems, but was not able to extract a solution. At least not a
solution which works without modifiing nimsuggest. With modifying nimsuggest,
there may be a few: Using port number 0, so that OS chooses a free port number.
Or maybe ensuring that client always closes socket connection first. Or maybe
setting SO_REUSEADDR flag before bind(). SO_LINGER flag with timeout 0 was also
mentioned, but not recommended.
https://github.com/ngtk3/NEd
$ ./ned test.nim
Traceback (most recent call last)
ned.nim(1362) showData
net.nim(1520) connect
os.nim(153) raiseOSError
Error: unhandled exception: Connection refused [OSError]
