AcceptError

    pub const AcceptError = error{
        /// The per-process limit on the number of open file descriptors has been reached.
        ProcessFdQuotaExceeded,
        /// The system-wide limit on the total number of open files has been reached.
        SystemFdQuotaExceeded,
        /// Not enough free memory. This often means that the memory allocation is limited
        /// by the socket buffer limits, not by the system memory.
        SystemResources,
        /// Either `listen` was never called, or `shutdown` was called (possibly while
        /// this call was blocking). This allows `shutdown` to be used as a concurrent
        /// cancellation mechanism.
        SocketNotListening,
        /// The network subsystem has failed.
        NetworkDown,
        /// No connection is already queued and ready to be accepted, and
        /// the socket is configured as non-blocking.
        WouldBlock,
        /// An incoming connection was indicated, but was subsequently terminated by the
        /// remote peer prior to accepting the call.
        ConnectionAborted,
        /// Firewall rules forbid connection.
        BlockedByFirewall,
        ProtocolFailure,
    } || Io.UnexpectedError || Io.Cancelable