[clisp-list] Re: socket problem: handling unexpected client disconnects

[Sam S. <sd...@gn...>]

>* Darken, Chris USA <pwq...@ac...il.zvy> [2003-09-07 06:47:36 -0700]:
>
> I have a CLISP program (CLISP 2.31 under WinXP) that sends characters
> to a client program over a socket.  My problem is that when the
> connection is lost (e.g. because the client program receiving the
> characters unexpectedly closes the connection on its end), my program
> exits either in a call to socket-status or in a write-char to the
> socket with an error like:
>  
> *** - Winsock error 10054 (ECONNRESET): Connection reset by peer
>  
> I don't know much about error handling under lisp, but I can't see how
> to catch this error.  I've searched the mailing list archive and
> haven't found a solution.
>  
> Can anyone tell me how my program could tolerate unexpected client
> disconnects without exiting?

I do not observe this with the native (mingw) port:

[3]> (setq s (ext:socket-server))
#<SOCKET-SERVER 0.0.0.0:4686>
[4]> (setq l (ext:socket-accept s))         ; telnet localhost 4686
#<IO UNBUFFERED SOCKET-STREAM CHARACTER 0.0.0.0:4686>
[5]> (ext:socket-status l)
:OUTPUT ;
1
[6]> (ext:socket-status l)                   ; close telnet
:APPEND ;
1
[7]>

i.e., :APPEND means :EOF on read (connection closed)


are you using cygwin?

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