source: branches/lib/GDE/MUSCLE/src/globalsosx.cpp

#ifdef __MACH__

#include <memory.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/sysctl.h>
#include <sys/socket.h>
#include <sys/gmon.h>
#include <mach/vm_param.h>
#include <netinet/in.h>
#include <netinet/icmp6.h>
#include <sys/vmmeter.h>
#include <sys/proc.h>
#include <mach/task_info.h>
#include <mach/task.h>
#include <mach/mach_init.h>
#include <mach/vm_statistics.h>

const double DEFAULT_RAM = 1e9;
const double DEFAULT_MEM_USE = 1e6;

double GetNAN()
        {
        static unsigned long nan[2]={0xffffffff, 0x7fffffff};
        double dNAN = *( double* )nan;
        return dNAN;
        }

double g_dNAN = GetNAN();


double GetRAMSize()
        {
        static double CACHED_RAM = 0;
        if (CACHED_RAM != 0)
                return CACHED_RAM;

        uint64_t MemPages = 0;
        size_t Len = sizeof(MemPages);
        if (sysctlbyname("hw.memsize", &MemPages, &Len, NULL, 0) < 0)
                return DEFAULT_RAM;
        return (double) MemPages;
        }

double GetRAMSizeMB()
        {
        return GetRAMSize()/1e6;
        }

static double g_uPeakMemUseBytes;

double GetMaxMemUseBytes()
        {
        return g_uPeakMemUseBytes;
        }

double GetPeakMemUseBytes()
        {
        return GetMaxMemUseBytes();
        }

double GetMemUseBytes()
        {
        task_t mytask = mach_task_self();
        struct task_basic_info ti;
        memset((void *) &ti, 0, sizeof(ti));
        mach_msg_type_number_t count = TASK_BASIC_INFO_COUNT;
        kern_return_t ok = task_info(mytask, TASK_BASIC_INFO, (task_info_t) &ti, &count);
        if (ok == KERN_INVALID_ARGUMENT)
                return DEFAULT_MEM_USE;

        if (ok != KERN_SUCCESS)
                return DEFAULT_MEM_USE;

        double uBytes = (double ) ti.resident_size;
        if (uBytes > g_uPeakMemUseBytes)
                g_uPeakMemUseBytes = uBytes;
        return uBytes;
        }

double GetMemUseMB()
        {
        return GetMemUseBytes()/1e6;
        }

void OSInit()
        {
        }

#endif // __MACH__