After sending the STOP signal to a process, it stops working as expected, but still accepts TCP connections. So is it working anyhow?
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1Sounds like the operating system is excepting them on your behalf, I think this happens to reduce latency.– ctrl-alt-delorSep 27, 2012 at 22:17
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1 Answer
Once a Unix process binds an IP address and port to a stream socket, the kernel begins accepting TCP connections for that address/port and continues until the socket is unbound or closed. The process gains access to the connections via the accept() system call, but the connections are happening regardless. Beyond the initial TCP handshake, the connection is idle until accept() is called and the process starts to use the connected socket. The kernel will also accept, buffer and acknowledge a system-specific amount of data before accept() is called.
So connections are occurring but there isn't any real activity (mail being sent, web pages being served, etc.) while the process is stopped.
answered Sep 28, 2012 at 0:14
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Sounds plausible. Just wanted to add there is activity. Data sent to the process over the connection is acknowledged. Sep 28, 2012 at 7:10