/**

* @file cpuusage.cpp

* @brief print out the percent cpu usage at a given interval

* @author Matthew McCormick (thewtex)

* @version

* @date 2009-08-12

*/

#include <fstream>

#include <iostream>

#include <sstream>

#include <string>

using namespace std;

#include <unistd.h> // sleep

// in seconds

const static unsigned int INTERVAL=1;

class CPUPercentage

};

CPUPercentage::CPUPercentage():

}

CPUPercentage::~CPUPercentage()

{

if(m_stat_file.is_open())

m_stat_file.close();

}

const float& CPUPercentage::get_percentage()

{

m_stat_file.open("/proc/stat");

getline(m_stat_file, m_stat_line);

m_stat_file.close();

// skip "cpu"

m_line_start_pos = m_stat_line.find_first_not_of(" ", 3);

m_line_end_pos = m_stat_line.find_first_of(' ', m_line_start_pos);

m_line_end_pos = m_stat_line.find_first_of(' ', m_line_end_pos + 1);

m_line_end_pos = m_stat_line.find_first_of(' ', m_line_end_pos + 1);

m_line_end_pos = m_stat_line.find_first_of(' ', m_line_end_pos + 1);

m_iss.str(m_stat_line.substr(m_line_start_pos, m_line_end_pos - m_line_start_pos));

m_iss >> m_next_user >> m_next_nice >> m_next_system >> m_next_idle;

m_iss.clear();

m_diff_user = m_next_user - m_current_user;

m_diff_system = m_next_system - m_current_system;

m_diff_nice = m_next_nice - m_current_nice;

m_diff_idle = m_next_idle - m_current_idle;

m_percentage = static_cast<float>(m_diff_user + m_diff_system + m_diff_nice)/static_cast<float>(m_diff_user + m_diff_system + m_diff_nice + m_diff_idle)*100.0;

m_current_user = m_next_user;

m_current_system = m_next_system;

m_current_nice = m_next_nice;

m_current_idle = m_next_idle;

return m_percentage;

}

int main(int argc, char** argv)

}