FBB::ClientSocket(3bobcat) Client Socket FBB::ClientSocket(3bobcat)

FBB::ClientSocket - 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.

Copy and move constructors (and assignment operators) are 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 <string>
#include <bobcat/clientsocket>
#include <bobcat/ifdstream>
#include <bobcat/ofdstream>
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 = stoul(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;
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

bobcat(7), ifdstream(3bobcat), ifdbuf(3bobcat), inetaddress(3bobcat), localclientsocket(3bobcat), ofdstream(3bobcat), ofdstream(3bobcat), serversocket(3bobcat), socketbase(3bobcat)

None Reported.

https://fbb-git.gitlab.io/bobcat/: gitlab project page;
bobcat_6.02.02-x.dsc: detached signature;
bobcat_6.02.02-x.tar.gz: source archive;
bobcat_6.02.02-x_i386.changes: change log;
libbobcat1_6.02.02-x_*.deb: debian package containing the libraries;
libbobcat1-dev_6.02.02-x_*.deb: debian package containing the libraries, headers and manual pages;

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 (f.b.brokken@rug.nl).

2005-2022 libbobcat-dev_6.02.02