Question

无论如何，使用C ++我可以获得有关计算机的基本信息吗？例如，有没有办法可以检查正在使用多少内存（整个计算机不仅仅是我的计算机），可用的总内存，虚拟内存使用情况，CPU使用率，网络统计数据等等？

我使用的是Mac OS X Snow Leopard，但我更喜欢可以为所有Mac OS（即Lion）实施的解决方案

Answer 1

对于MacOS / X下的系统范围内存使用信息，打开并读取文件/ usr / bin / vm_stat，如下所示：

static double ParseMemValue(const char * b)
{
   while((*b)&&(isdigit(*b) == false)) b++;
   return isdigit(*b) ? atof(b) : -1.0;
}

// Returns a number between 0.0f and 1.0f, with 0.0f meaning all RAM is available, and 1.0f meaning all RAM is currently in use
float GetSystemMemoryUsagePercentage()
{
   FILE * fpIn = popen("/usr/bin/vm_stat", "r");
   if (fpIn)
   {
      double pagesUsed = 0.0, totalPages = 0.0;
      char buf[512];
      while(fgets(buf, sizeof(buf), fpIn) != NULL)
      {
         if (strncmp(buf, "Pages", 5) == 0)
         {
            double val = ParseMemValue(buf);
            if (val >= 0.0)
            {
               if ((strncmp(buf, "Pages wired", 11) == 0)||(strncmp(buf, "Pages active", 12) == 0)) pagesUsed += val;
               totalPages += val;
            }
         }
         else if (strncmp(buf, "Mach Virtual Memory Statistics", 30) != 0) break;  // Stop at "Translation Faults", we don't care about anything at or below that
      }
      pclose(fpIn);

      if (totalPages > 0.0) return (float) (pagesUsed/totalPages);
   }
   return -1.0f;  // indicate failure
}

对于CPU使用率指标，请执行以下操作：

#include <mach/mach_init.h>
#include <mach/mach_error.h>
#include <mach/mach_host.h>
#include <mach/vm_map.h>

static unsigned long long _previousTotalTicks = 0;
static unsigned long long _previousIdleTicks = 0;

// Returns 1.0f for "CPU fully pinned", 0.0f for "CPU idle", or somewhere in between
// You'll need to call this at regular intervals, since it measures the load between
// the previous call and the current one.
float GetCPULoad()
{
   host_cpu_load_info_data_t cpuinfo;
   mach_msg_type_number_t count = HOST_CPU_LOAD_INFO_COUNT;
   if (host_statistics(mach_host_self(), HOST_CPU_LOAD_INFO, (host_info_t)&cpuinfo, &count) == KERN_SUCCESS)
   {
      unsigned long long totalTicks = 0;
      for(int i=0; i<CPU_STATE_MAX; i++) totalTicks += cpuinfo.cpu_ticks[i];
      return CalculateCPULoad(cpuinfo.cpu_ticks[CPU_STATE_IDLE], totalTicks);
   }
   else return -1.0f;
}

float CalculateCPULoad(unsigned long long idleTicks, unsigned long long totalTicks)
{
  unsigned long long totalTicksSinceLastTime = totalTicks-_previousTotalTicks;
  unsigned long long idleTicksSinceLastTime  = idleTicks-_previousIdleTicks;
  float ret = 1.0f-((totalTicksSinceLastTime > 0) ? ((float)idleTicksSinceLastTime)/totalTicksSinceLastTime : 0);
  _previousTotalTicks = totalTicks;
  _previousIdleTicks  = idleTicks;
  return ret;
}

对于网络统计，我不知道解决方案（除了可能运行netstat并以某种方式解析结果......这取决于我认为你感兴趣的网络统计数据。）

Answer 2

首先，如果您只关注Mac OS，那么选择的语言应该是Objective - C。

您需要遵循的步骤

学习Obj-C，不是那么难，我自己来自c ++背景，经过几个星期用这种语言在平台上工作后我变得非常流利
检查Mac OSX开发人员库：Mac OS X Developer Library
查看this
和this

在MacOS X上检索系统信息？

2 个答案: