Author vstinner
Recipients alex, christian.heimes, dstufft, janssen, martin.panter, pitrou, vstinner
Date 2017-07-03.08:28:09
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <1499070490.33.0.0125454606894.issue30319@psf.upfronthosting.co.za>
In-reply-to
Content
tl; dr I agree to ignore ECONNRESET-like errors on socket.shutdown() and sock.close().

I'm not sure that I understand *exactly* the problem here. In which case closing a socket fails with ECONNRESET? Can it mean that the last write() was buffered and failed?

If socket.send() is blocking, I expect that send() gets the ECONNRESET error.

If socket.send() is non-blocking, the application has to be very carefully written to handle many kinds of errors.

From a high lever point of view, I don't think that ECONNRESET is interested. I expect that a protocol at the application level doesn't rely on ECONNRESET, but a command like "QUIT". No?

For a file on disk, it's different, since write() is always buffered and close() has to flush pending write on disk.

For a network protocol, loosing the connection, loosing data, etc. is something "normal", not something execptional. That's why there are application-level commands to close cleanly a connection.

Ok, now for SSL sockets... Is it also ok to ignore ECONNRESET on sock.close() for an SSL socket?

--

ECONNRESET can occur on sock.close(), but not only: see bpo-30329, shutdown() fails can ENOTCONN on UNIX or WSAEINVAL on Windows. I modified poplib and imaplib recently to handle WSAEINVAL:

commit 83a2c2879839da2e10037f5e4af1bd1dafbf1a52
Author: Victor Stinner <victor.stinner@gmail.com>
Date:   Mon May 15 17:33:45 2017 +0200

    bpo-30329: Catch Windows error 10022 on shutdown() (#1538)
    
    Catch the Windows socket WSAEINVAL error (code 10022) in imaplib and
    poplib on shutdown(SHUT_RDWR): An invalid operation was attempted
    
    This error occurs sometimes on SSL connections.
History
Date User Action Args
2017-07-03 08:28:10vstinnersetrecipients: + vstinner, janssen, pitrou, christian.heimes, alex, martin.panter, dstufft
2017-07-03 08:28:10vstinnersetmessageid: <1499070490.33.0.0125454606894.issue30319@psf.upfronthosting.co.za>
2017-07-03 08:28:10vstinnerlinkissue30319 messages
2017-07-03 08:28:09vstinnercreate