Jay Loden wrote: > Roy Smith wrote: >> In article <[EMAIL PROTECTED]>, >> billiejoex <[EMAIL PROTECTED]> wrote: >> >>> Hi there. >>> I'm setting up test suite for a project of mine. >>> >From test suite, acting as a client, I'd like to know, in certain >>> situations, if the socket is closed on the other end or not. >>> I noticed that I can "detect" such state if a call to socket.read() >>> returns 0 but it seems a little poor to me. :-\ >>> Is there a reliable way to test such socket 'state'? >> This isn't really a Python question, it's a Berkeley Socket API question. >> You don't say, but I assume you're talking about a TCP (i.e. SOCKSTREAM) >> connection? >> >> The answer is you can use the select() system call to detect "exceptional >> conditions" on a socket. Python's select module provides this >> functionality, but to understand how to use it, you need to study the >> underlying API. > > Thanks for the interesting information and suggestion of using select(). You > are correct that this is actually mostly a socket API question but pertains > to Python since the code is all Python's socket and asyncore modules. It > might help to step back and explain the original problem. The goal of this > portion of the test suite we are writing for the project is to determine if a > remote server is behaving properly by closing a socket from the server side > based on a client-side command. > > Really what's needed is a way to make sure the socket gets closed, and > preferably determine if it was closed from the remote end as expected. Do you > know if this is possible to determine from the client side > reliably/accurately? Would select()'s exceptional condition flag actually > indicate whether or not the root cause of the condition was a socket closed > by the remote peer? I've read through the select's manpage and I can't seem > to find a reference that indicates what the possible values are for the I/O > descriptor sets returned by select. Is there another man page, or a place in > the header file for select I can look?
Use select to determine if the socket is readable and writable. If it is, yet you can't send or receive to/from it, then it is closed. - Josiah -- http://mail.python.org/mailman/listinfo/python-list
