+ double pages = pss.physical_memory;
+ double pagesize = pss.page_size;
+ if (0 <= pages && 0 <= pagesize)
+ return pages * pagesize;
+ }
+ }
+#endif
+
+#if HAVE_SYSMP && defined MP_SAGET && defined MPSA_RMINFO && defined _SC_PAGESIZE
+ { /* This works on irix6. */
+ struct rminfo realmem;
+ if (sysmp (MP_SAGET, MPSA_RMINFO, &realmem, sizeof realmem) == 0)
+ {
+ double pagesize = sysconf (_SC_PAGESIZE);
+ double pages = realmem.physmem;
+ if (0 <= pages && 0 <= pagesize)
+ return pages * pagesize;
+ }
+ }
+#endif
+
+#if HAVE_GETSYSINFO && defined GSI_PHYSMEM
+ { /* This works on Tru64 UNIX V4/5. */
+ int physmem;
+
+ if (getsysinfo (GSI_PHYSMEM, (caddr_t) &physmem, sizeof (physmem),
+ NULL, NULL, NULL) == 1)
+ {
+ double kbytes = physmem;
+
+ if (0 <= kbytes)
+ return kbytes * 1024.0;
+ }
+ }
+#endif
+
+#if HAVE_SYSCTL && defined HW_PHYSMEM
+ { /* This works on *bsd and darwin. */
+ unsigned int physmem;
+ size_t len = sizeof physmem;
+ static int mib[2] = { CTL_HW, HW_PHYSMEM };
+
+ if (sysctl (mib, ARRAY_SIZE (mib), &physmem, &len, NULL, 0) == 0
+ && len == sizeof (physmem))
+ return (double) physmem;
+ }
+#endif
+
+#if HAVE__SYSTEM_CONFIGURATION
+ /* This works on AIX. */
+ return _system_configuration.physmem;
+#endif
+
+#if defined _WIN32
+ { /* this works on windows */
+ PFN_MS_EX pfnex;
+ HMODULE h = GetModuleHandle ("kernel32.dll");
+
+ if (!h)
+ return 0.0;
+
+ /* Use GlobalMemoryStatusEx if available. */
+ if ((pfnex = (PFN_MS_EX) GetProcAddress (h, "GlobalMemoryStatusEx")))
+ {
+ lMEMORYSTATUSEX lms_ex;
+ lms_ex.dwLength = sizeof lms_ex;
+ if (!pfnex (&lms_ex))
+ return 0.0;
+ return (double) lms_ex.ullTotalPhys;
+ }
+
+ /* Fall back to GlobalMemoryStatus which is always available.
+ but returns wrong results for physical memory > 4GB. */
+ else
+ {
+ MEMORYSTATUS ms;
+ GlobalMemoryStatus (&ms);
+ return (double) ms.dwTotalPhys;