Qt TCP/IP socket connection check -

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i writing qt tcp/ip client. want check connection state server before send data sever. far knowledge can following methods

  • use bool 'connectionstate', set variable when connected sever , reset variable on disconnected() signal. before sending data server (client->write()) check value of variable.
  • use 'client->state() == qtcpsocket::connectedstate' way check connection state.

which practice. or other method this.

thanks in advance.

qtcpsocket derived qabstractsocket, provides state() function. returns 1 of following enums: -

enum socketstate { unconnectedstate, hostlookupstate, connectingstate, connectedstate, ..., listeningstate }

so, assuming m_psocket qtcpsocket, check if connected:-

bool connected = (m_psocket->state() == qtcpsocket::connectedstate);

you add boolean , keep track of state, if network error occurs need ensure in-sync actual connection state.


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