獲取系統CPU、內存和IO信息

process_stat.h的內容如下： 

/** @file 
* @brief 進程統計信息函數的聲明 
* @author 張亞霏 
* @date 2009/05/03 
* @version 0.1 
* 
*/  
#ifndef PROCESS_STAT_H  
#define PROCESS_STAT_H  

#ifdef __cplusplus  
extern "C" {  
#endif  

    typedef long long           int64_t;  
    typedef unsigned long long  uint64_t;  

    /// 獲取當前進程的cpu使用率，返回-1失敗  
    int get_cpu_usage();  

    /// 獲取當前進程內存和虛擬內存使用量，返回-1失敗，0成功  
    int get_memory_usage(uint64_t* mem, uint64_t* vmem);  

    /// 獲取當前進程總共讀和寫的IO字節數，返回-1失敗，0成功  
    int get_io_bytes(uint64_t* read_bytes, uint64_t* write_bytes);  

#ifdef  __cplusplus  
}  
#endif  

#endif/*PROCESS_STAT_H*/  

process_stat_win.c的內容如下： 
/** @file 
* @brief 進程統計信息函數的實現 
* @author 張亞霏 
* @date 2009/05/03 
* @version 0.1 
* 
* 部分代碼來自MSDN的例子 
* 部分代碼來自google chromium項目 
* 
* 需要連接到psapi.lib 
*/  

#include <windows.h>  
#include <psapi.h>  
#include <assert.h>  
#include "process_stat.h"  

/// 時間轉換  
static uint64_t file_time_2_utc(const FILETIME* ftime)  
{  
    LARGE_INTEGER li;  

    assert(ftime);  
    li.LowPart = ftime->dwLowDateTime;  
    li.HighPart = ftime->dwHighDateTime;  
    return li.QuadPart;  
}  

/// 獲得CPU的核數  
static int get_processor_number()  
{  
    SYSTEM_INFO info;  
    GetSystemInfo(&info);  
    return (int)info.dwNumberOfProcessors;  
}  

int get_cpu_usage()  
{  
    //cpu數量  
    static int processor_count_ = -1;  
    //上一次的時間  
    static int64_t last_time_ = 0;  
    static int64_t last_system_time_ = 0;  

    FILETIME now;  
    FILETIME creation_time;  
    FILETIME exit_time;  
    FILETIME kernel_time;  
    FILETIME user_time;  
    int64_t system_time;  
    int64_t time;  
    int64_t system_time_delta;  
    int64_t time_delta;  

    int cpu = -1;  

    if(processor_count_ == -1)  
    {  
        processor_count_ = get_processor_number();  
    }  

    GetSystemTimeAsFileTime(&now);  

    if (!GetProcessTimes(GetCurrentProcess(), &creation_time, &exit_time,  
        &kernel_time, &user_time))  
    {  
        // We don't assert here because in some cases (such as in the Task   

        Manager)  
            // we may call this function on a process that has just exited but   

            we have  
            // not yet received the notification.  
            return -1;  
    }  
    system_time = (file_time_2_utc(&kernel_time) + file_time_2_utc(&user_time)) /   processor_count_;  
    time = file_time_2_utc(&now);  

    if ((last_system_time_ == 0) || (last_time_ == 0))  
    {  
        // First call, just set the last values.  
        last_system_time_ = system_time;  
        last_time_ = time;  
        return -1;  
    }  

    system_time_delta = system_time - last_system_time_;  
    time_delta = time - last_time_;  

    assert(time_delta != 0);  

    if (time_delta == 0)  
        return -1;  

    // We add time_delta / 2 so the result is rounded.  
    cpu = (int)((system_time_delta * 100 + time_delta / 2) / time_delta);  
    last_system_time_ = system_time;  
    last_time_ = time;  
    return cpu;  
}  

int get_memory_usage(uint64_t* mem, uint64_t* vmem)  
{  
    PROCESS_MEMORY_COUNTERS pmc;  
    if(GetProcessMemoryInfo(GetCurrentProcess(), &pmc, sizeof(pmc)))  
    {  
        if(mem) *mem = pmc.WorkingSetSize;  
        if(vmem) *vmem = pmc.PagefileUsage;  
        return 0;  
    }  
    return -1;  
}  

int get_io_bytes(uint64_t* read_bytes, uint64_t* write_bytes)  
{  
    IO_COUNTERS io_counter;  
    if(GetProcessIoCounters(GetCurrentProcess(), &io_counter))  
    {  
        if(read_bytes) *read_bytes = io_counter.ReadTransferCount;  
        if(write_bytes) *write_bytes = io_counter.WriteTransferCount;  
        return 0;  
    }  
    return -1;  
}  

可以這樣使用： 
/** @file 
* @brief 進程統計信息函數的測試 
* @author 張亞霏 
* @date 2009/05/03 
* @version 0.1 
* 
*/  
#include "process_stat.h"  
#include <stdio.h>  
#include <Windows.h>  

int main()   
{   
    while(1)   
    {  
        int cpu;  
        uint64_t mem, vmem, r, w;  

        cpu = get_cpu_usage();  
        get_memory_usage(&mem, &vmem);  
        get_io_bytes(&r, &w);  

        printf("CPU使用率: %u\n",cpu);  
        printf("內存使用: %u 字節\n", mem);  
        printf("虛擬內存使用: %u 字節\n", vmem);  
        printf("總共讀: %u 字節\n", r);  
        printf("總共寫: %u 字節\n", w);   

        Sleep(1000);   
    }   
    return 0;   
}