CPU/ RAM USAGE/ Temperature

[Argy]

Hi, i would like to ask you something.
I want to make an application that will check CPU/RAM USAGE and CPU TEMPERATURE and if it meets some requirements it will restart your system or do something else..

but my problem is:

1) How do i get that info? (i know that in VB.net there is an easy way) but in C/C++ or Java?
2) Is it possible though a C program to execute a command and parse that info to your program?

I am mainly interested for windows but i need also info for linux too..

[JLBorges]

> Is it possible though a C program to execute a command and parse that info to your program?

Yes. The simplest way may be to redirect the output of the external program to a file.

#include <iostream>
#include <cstdlib>
#include <fstream>

int main()
{
    // http://en.cppreference.com/w/cpp/utility/program/system
    std::system( "/usr/bin/top -b -n 1 | /usr/bin/head -n5 > /tmp/result.txt" );
    
    std::cout << "top result summary\n-----------------\n" 
              << std::ifstream( "/tmp/result.txt" ).rdbuf() ; 
}

http://coliru.stacked-crooked.com/a/ac38d3e9a11380c9

[Argy]

Ok i managed to do that..But still my first question>??
if someone can give me any info that would be great :)

[JLBorges]

Unix: http://www.freebsd.org/cgi/man.cgi?query=sysctl&apropos=0&sektion=0&manpath=FreeBSD+10.1-RELEASE&arch=default&format=html

Windows: http://technet.microsoft.com/en-us/library/cc753182.aspx

[modoran]

Memory usage -> GlobalMemoryStatusEx
http://msdn.microsoft.com/en-us/library/windows/desktop/aa366589(v=vs.85).aspx

Total CPU usage:

#include "TCHAR.h"
#include "pdh.h"

static PDH_HQUERY cpuQuery;
static PDH_HCOUNTER cpuTotal;

void init() {
    PdhOpenQuery(NULL, NULL, &cpuQuery);
    PdhAddCounter(cpuQuery, L"\\Processor(_Total)\\% Processor Time", NULL, &cpuTotal);
    PdhCollectQueryData(cpuQuery);
}

double getCurrentValue() {
    PDH_FMT_COUNTERVALUE counterVal;

    PdhCollectQueryData(cpuQuery);
    PdhGetFormattedCounterValue(cpuTotal, PDH_FMT_DOUBLE, NULL, &counterVal);
    return counterVal.doubleValue;
}

For CPU temperature use WMI -> MSAcpi_ThermalZoneTemperature class:

#define _WIN32_DCOM
#include <iostream>
using namespace std;
#include <comdef.h>
#include <Wbemidl.h>
 
#pragma comment(lib, "wbemuuid.lib")
 
HRESULT GetCpuTemperature(LPLONG pTemperature)
{
        if (pTemperature == NULL)
                return E_INVALIDARG;
 
        *pTemperature = -1;
        HRESULT ci = CoInitialize(NULL);
        HRESULT hr = CoInitializeSecurity(NULL, -1, NULL, NULL, RPC_C_AUTHN_LEVEL_DEFAULT, RPC_C_IMP_LEVEL_IMPERSONATE, NULL, EOAC_NONE, NULL);
        if (SUCCEEDED(hr))
        {
                IWbemLocator *pLocator;
                hr = CoCreateInstance(CLSID_WbemAdministrativeLocator, NULL, CLSCTX_INPROC_SERVER, IID_IWbemLocator, (LPVOID*)&pLocator);
                if (SUCCEEDED(hr))
                {
                        IWbemServices *pServices;
                        BSTR ns = SysAllocString(L"root\\WMI");
                        hr = pLocator->ConnectServer(ns, NULL, NULL, NULL, 0, NULL, NULL, &pServices);
                        pLocator->Release();
                        SysFreeString(ns);
                        if (SUCCEEDED(hr))
                        {
                                BSTR query = SysAllocString(L"SELECT * FROM MSAcpi_ThermalZoneTemperature");
                                BSTR wql = SysAllocString(L"WQL");
                                IEnumWbemClassObject *pEnum;
                                hr = pServices->ExecQuery(wql, query, WBEM_FLAG_RETURN_IMMEDIATELY | WBEM_FLAG_FORWARD_ONLY, NULL, &pEnum);
                                SysFreeString(wql);
                                SysFreeString(query);
                                pServices->Release();
                                if (SUCCEEDED(hr))
                                {
                                        IWbemClassObject *pObject;
                                        ULONG returned;
                                        hr = pEnum->Next(WBEM_INFINITE, 1, &pObject, &returned);
                                        pEnum->Release();
                                        if (SUCCEEDED(hr))
                                        {
                                                BSTR temp = SysAllocString(L"CurrentTemperature");
                                                VARIANT v;
                                                VariantInit(&v);
                                                hr = pObject->Get(temp, 0, &v, NULL, NULL);
                                                pObject->Release();
                                                SysFreeString(temp);
                                                if (SUCCEEDED(hr))
                                                {
                                                        *pTemperature = V_I4(&v);
                                                }
                                                VariantClear(&v);
                                        }
                                }
                        }
                        if (ci == S_OK)
                        {
                                CoUninitialize();
                        }
                }
        }
        return hr;
}
 
int main(int argc, char **argv)
{
        LONG temp;
        GetCpuTemperature(&temp);
        printf("temp=%lf\n", ((double)temp / 10 - 273.15));
        getc(stdin);
        return 0;
}