FBB::ClientSocket(3) Client Socket connecting to a Server in the Internet


#include <bobcat/clientsocket>
Linking option: -lbobcat


An FBB::ClientSocket may be constructed to connect to some server process in the internet. The socket made available by the FBB:ClientSocket may be used to initialize a std::istream and/or std::ostream. The std::istream is used to read information from the server process to which the FBB::ClientSocket connects, The std::ostream is used to send information to the server process to which the FBB::ClientSocket connects. Since a socket may be considered a file descriptor the available FBB::IFdStream, FBB::IFdStreamBuf, FBB::OFdStream, and FBB::OFdStreamBuf classes may be used profitably here. Note that having available a socket does not mean that this defines the communication protocol. It is (still) the responsibility of the programmer to comply with an existing protocol or to implement a tailor-made protocol. The latter situation implies that the sequence of input- and output operations is defined by the programmer.

A Unix Domain client socket can be defined using FBB::LocalClientSocket.


All constructors, members, operators and manipulators, mentioned in this man-page, are defined in the namespace FBB.




  • ClientSocket(std::string const &host, uint16_t port):
    This constructor initializes an FBB::ClientSocket object, preparing it for a connection to the specified port at the given host. An FBB::Exception is thrown if the socket could not be constructed. The construction of the socket does not mean that a connection has actually been established. In order to connect to the server, the member connect() (see below) should be used. The copy constructor is not available.


All members of FBB::SocketBase (and thus of FBB::InetAddress) are available, as FBB::ClientSocket inherits from these classes.
  • int connect():
    This member returns a socket that can be used to communicate with the server process. An FBB::Exception exception is thrown if the connection could not be established or if the SocketBase base class could not properly be constructed.


See also the serversocket(3bobcat) example.
    #include <iostream>
    #include <bobcat/clientsocket>
    #include <bobcat/ifdstream>
    #include <bobcat/ofdstream>
    #include <bobcat/a2x>
    using namespace std;
    using namespace FBB;
    int main(int argc, char **argv)
        if (argc == 1)
            cerr << "Provide servername and port number\n";
            return 1;
        size_t     port = A2x(argv[2]);
        ClientSocket client(argv[1], port);
        int fd = client.connect();
        string line;
        cout << "Connecting to socket " << fd << endl <<
                "address = " << client.dottedDecimalAddress() << ", " << 
                                                                 endl <<
                "communication through port " << client.port() << endl;
        IFdStream in(fd);                 // stream to read from        
        OFdStream out(fd);                // stream to write to
        while (true)
                                    // Ask for a textline, stop if 
            cout << "? ";           // empty / none
            if (!getline(cin, line) || line.length() == 0)
                return 0;
            cout << "Line read: " << line << endl;
                                    // Return the line to the server
            out << line.c_str() << endl;    
            cout << "wrote line\n";
            getline(in, line);      // Wait for a reply from the server
            cout << "Answer: " << line << endl;
        return 0;
    catch (Exception const &err)
        cerr << err.what() << "\n" <<
                "Can't connect to " << argv[1] << ", port " << 
                argv[2] << endl;
        return 1;


bobcat/clientsocket - defines the class interface


None Reported.


  • bobcat_4.02.00-x.dsc: detached signature;
  • bobcat_4.02.00-x.tar.gz: source archive;
  • bobcat_4.02.00-x_i386.changes: change log;
  • libbobcat1_4.02.00-x_*.deb: debian package holding the libraries;
  • libbobcat1-dev_4.02.00-x_*.deb: debian package holding the libraries, headers and manual pages;
  • http://sourceforge.net/projects/bobcat: public archive location;


Bobcat is an acronym of `Brokken's Own Base Classes And Templates'.


This is free software, distributed under the terms of the GNU General Public License (GPL).


Frank B. Brokken ([email protected]).