看到好多朋友询问怎样得到系统信息（象任务管理器一样），前段时间研究了一番，有所领悟，现与大家共享。
下面是部分测试代码:
#include <windows.h>
#include <stdio.h>
#include <conio.h>
#include <tchar.h>
#include <pdh.h>
#define MAXPATH 80
int __cdecl _tmain (int argc, TCHAR **argv)
{
HQUERY hQuery;
HCOUNTER *pCounterHandle;
PDH_STATUS pdhStatus;
PDH_FMT_COUNTERVALUE fmtValue;
DWORD ctrType;
CHAR szPathBuffer[MAXPATH] = {'\0'};
int nRetCode = 0;
// Open the query object.
pdhStatus = PdhOpenQuery (0, 0, &hQuery);
pCounterHandle = (HCOUNTER *)GlobalAlloc(GPTR, sizeof(HCOUNTER));
/*
\\Processor(_Total)\\% Processor Time CPU使用率
\\System\\Processes 当前系统进程数
\\System\\Threads 当前系统线程数
\\Memory\\Commit Limit 总共内存数K (包括虚拟内存)
\\Memory\\Committed Bytes 已用内存数K (包括虚拟内存)
\\TCP\\Connections Active 系统中已建立的 TCP连接个数
其它Object Items 可以利用PdhEnumObjects()和PdhEnumObjectItems()得到
反正我只要用到上面的东东:)
*/
strcat(szPathBuffer,"\\System\\Processes");
pdhStatus = PdhAddCounter (hQuery,
szPathBuffer,
0,
pCounterHandle);
// "Prime" counters that need two values to display a
// formatted value.
pdhStatus = PdhCollectQueryData (hQuery);
// Get the current value of this counter.
pdhStatus = PdhGetFormattedCounterValue (*pCounterHandle,
PDH_FMT_DOUBLE,
&ctrType,
&fmtValue);
//fmtValue.doubleValue为所要的结果
if (pdhStatus == ERROR_SUCCESS) {
printf (TEXT(",\"%.20g\"\n"), fmtValue.doubleValue);
}
else {
// Print the error value.
printf (TEXT("error.\"-1\""));
}
// Close the query.
pdhStatus = PdhCloseQuery (hQuery);
return nRetCode;
}
