Here is an example with popen. I would love a better solution, so if there is a socket or other method which does not resort to a shell call, I would greatly appreciate it. This should run with just g++ ping_demo.cpp -o ping_demo. Let me know if it causes compile errors.
// C++ Libraries
#include <cstdio>
#include <iostream>
#include <sstream>
#include <string>
/**
* @brief Convert String to Number
*/
template <typename TP>
TP str2num( std::string const& value ){
std::stringstream sin;
sin << value;
TP output;
sin >> output;
return output;
}
/**
* @brief Convert number to string
*/
template <typename TP>
std::string num2str( TP const& value ){
std::stringstream sin;
sin << value;
return sin.str();
}
/**
* @brief Execute Generic Shell Command
*
* @param[in] command Command to execute.
* @param[out] output Shell output.
* @param[in] mode read/write access
*
* @return 0 for success, 1 otherwise.
*
*/
int Execute_Command( const std::string& command,
std::string& output,
const std::string& mode = "r")
{
// Create the stringstream
std::stringstream sout;
// Run Popen
FILE *in;
char buff[512];
// Test output
if(!(in = popen(command.c_str(), mode.c_str()))){
return 1;
}
// Parse output
while(fgets(buff, sizeof(buff), in)!=NULL){
sout << buff;
}
// Close
int exit_code = pclose(in);
// set output
output = sout.str();
// Return exit code
return exit_code;
}
/**
* @brief Ping
*
* @param[in] address Address to ping.
* @param[in] max_attempts Number of attempts to try and ping.
* @param[out] details Details of failure if one occurs.
*
* @return True if responsive, false otherwise.
*
* @note { I am redirecting stderr to stdout. I would recommend
* capturing this information separately.}
*/
bool Ping( const std::string& address,
const int& max_attempts,
std::string& details )
{
// Format a command string
std::string command = "ping -c " + num2str(max_attempts) + " " + address + " 2>&1";
std::string output;
// Execute the ping command
int code = Execute_Command( command, details );
return (code == 0);
}
/**
* @brief Main Function
*/
int main( int argc, char* argv[] )
{
// Parse input
if( argc < 2 ){
std::cerr << "usage: " << argv[0] << " <address> <max-attempts = 3>" << std::endl;
return 1;
}
// Get the address
std::string host = argv[1];
// Get the max attempts
int max_attempts = 1;
if( argc > 2 ){
max_attempts = str2num<int>(argv[2]);
}
if( max_attempts < 1 ){
std::cerr << "max-attempts must be > 0" << std::endl;
return 1;
}
// Execute the command
std::string details;
bool result = Ping( host, max_attempts, details );
// Print the result
std::cout << host << " ";
if( result == true ){
std::cout << " is responding." << std::endl;
}
else{
std::cout << " is not responding. Cause: " << details << std::endl;
}
return 0;
}
Sample outputs
$> g++ ping_demo.cpp -o ping_demo
$> # Valid Example
$> ./ping_demo localhost
localhost is responding.
$> # Invalid Example
$> ./ping_demo localhostt
localhostt is not responding. Cause: ping: unknown host localhostt
$> # Valid Example
$> ./ping_demo 8.8.8.8
8.8.8.8 is responding.
