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copied!<p>The <a href="http://en.wikipedia.org/wiki/Ping" rel="nofollow noreferrer">ping</a> tool is usually implemented in C and works by sending <a href="http://en.wikipedia.org/wiki/Internet_Control_Message_Protocol" rel="nofollow noreferrer">ICMP</a> <a href="http://en.wikipedia.org/wiki/Ping#Echo_request" rel="nofollow noreferrer">Echo request</a> packets over a <a href="http://en.wikipedia.org/wiki/Raw_socket" rel="nofollow noreferrer">raw socket</a>,. The system time is recorded -- usually with <a href="http://www.opengroup.org/onlinepubs/000095399/functions/gettimeofday.html" rel="nofollow noreferrer">gettimeofday</a> on under <a href="http://en.wikipedia.org/wiki/POSIX" rel="nofollow noreferrer">posix</a> -- when the Echo request is made and again when an <a href="http://en.wikipedia.org/wiki/Ping#Echo_reply" rel="nofollow noreferrer">Echo reply</a> (if any) is received to determine the round-trip time. You can put the same functionality in your C++ application using <a href="http://beej.us/guide/bgnet/output/html/singlepage/bgnet.html#theory" rel="nofollow noreferrer">sockets</a>.</p> <p>Otherwise, extracting the information from a ping system call is probably easier than you think. The key is to open a <a href="http://en.wikipedia.org/wiki/Pipeline_(Unix)" rel="nofollow noreferrer">pipe</a> to allow reading of the <a href="http://en.wikipedia.org/wiki/Stdout#Standard_output_.28stdout.29" rel="nofollow noreferrer">standard output</a> of the ping command (see <a href="http://opengroup.org/onlinepubs/007908775/xsh/popen.html" rel="nofollow noreferrer"><code>popen</code></a> or <a href="http://msdn.microsoft.com/en-us/library/96ayss4b(VS.80).aspx" rel="nofollow noreferrer"><code>_popen</code></a>). A <a href="http://en.wikipedia.org/wiki/Regular_expression" rel="nofollow noreferrer">regular expression</a> (e.g. "time=([0-9]*)") could be used to pluck out the desired data. If you don't have a regex library available, then extracting this data only requires fairly trivial string manipulation. The <a href="http://www.sgi.com/tech/stl/basic_string.html" rel="nofollow noreferrer">STL string class</a> provides several algorithms that may be of use.</p>

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