TcpStream always terminates connections successfully (even on panic)

libs
15

Summarizing:

  • According to Internet Standard STD 7 (aka RFC 793), TCP connections can be closed by applications in two ways:
    • close (sending FIN)
    • abort (sending RST)
  • Peer applications can distinguish whether a connection was successfully closed (they receive an EOF) or was aborted (they receive an error).
  • Aborting a connection may cause data that has already been sent to be lost (which also avoids trying to flush out data that has not been confirmed by the peer yet).
  • Libc under Linux and FreeBSD provide a way to abort connections (using setsockopt with SO_LINGER).
  • The current implementation in Rust's standard library in combination with libc behavior on at least Linux and FreeBSD never aborts a connection (not even on panic) but always uses "close" (as defined in STD 7). Moreover, it is not possible to change this behavior without manually changing socket options using other libraries or C functions.

Thus my question is: should this behavior be changed? And if yes, how?

And: does anyone know how other high-level interfaces or applications typically handle this?

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