移植可能な方法でこれを行うために私が書いたコードを次に示します。完璧ではありませんが、少なくともいくつかのプラットフォームのそれぞれでこれを行う方法へのポインタを与えるべきだと思います.
(追記:私は OSX と Linux を定期的に使用しており、これがうまく機能することを知っています。Windows を使用することはめったにないため、Windows 条項には警告が適用されますが、それは正しいと思います。)
#ifdef __linux__
# include <sys/sysinfo.h>
#endif
#ifdef __APPLE__
# include <mach/task.h>
# include <mach/mach_init.h>
#endif
#ifdef _WINDOWS
# include <windows.h>
#else
# include <sys/resource.h>
#endif
/// The amount of memory currently being used by this process, in bytes.
/// By default, returns the full virtual arena, but if resident=true,
/// it will report just the resident set in RAM (if supported on that OS).
size_t memory_used (bool resident=false)
{
#if defined(__linux__)
// Ugh, getrusage doesn't work well on Linux. Try grabbing info
// directly from the /proc pseudo-filesystem. Reading from
// /proc/self/statm gives info on your own process, as one line of
// numbers that are: virtual mem program size, resident set size,
// shared pages, text/code, data/stack, library, dirty pages. The
// mem sizes should all be multiplied by the page size.
size_t size = 0;
FILE *file = fopen("/proc/self/statm", "r");
if (file) {
unsigned long vm = 0;
fscanf (file, "%ul", &vm); // Just need the first num: vm size
fclose (file);
size = (size_t)vm * getpagesize();
}
return size;
#elif defined(__APPLE__)
// Inspired by:
// http://miknight.blogspot.com/2005/11/resident-set-size-in-mac-os-x.html
struct task_basic_info t_info;
mach_msg_type_number_t t_info_count = TASK_BASIC_INFO_COUNT;
task_info(current_task(), TASK_BASIC_INFO, (task_info_t)&t_info, &t_info_count);
size_t size = (resident ? t_info.resident_size : t_info.virtual_size);
return size;
#elif defined(_WINDOWS)
// According to MSDN...
PROCESS_MEMORY_COUNTERS counters;
if (GetProcessMemoryInfo (GetCurrentProcess(), &counters, sizeof (counters)))
return counters.PagefileUsage;
else return 0;
#else
// No idea what platform this is
return 0; // Punt
#endif
}