Function: memory-info

memory-info is a function defined in alloc.c.

Signature

(memory-info)

Documentation

Return a list of (TOTAL-RAM FREE-RAM TOTAL-SWAP FREE-SWAP).

All values are in Kbytes. If there is no swap space, last two values are zero. If the system is not supported or memory information can't be obtained, return nil.

Source Code

// Defined in /usr/src/emacs/src/alloc.c
{
#if defined HAVE_LINUX_SYSINFO
  struct sysinfo si;
  uintmax_t units;

  if (sysinfo (&si))
    return Qnil;
#ifdef LINUX_SYSINFO_UNIT
  units = si.mem_unit;
#else
  units = 1;
#endif
  return list4i ((uintmax_t) si.totalram * units / 1024,
		 (uintmax_t) si.freeram * units / 1024,
		 (uintmax_t) si.totalswap * units / 1024,
		 (uintmax_t) si.freeswap * units / 1024);
#elif defined WINDOWSNT
  unsigned long long totalram, freeram, totalswap, freeswap;

  if (w32_memory_info (&totalram, &freeram, &totalswap, &freeswap) == 0)
    return list4i ((uintmax_t) totalram / 1024,
		   (uintmax_t) freeram / 1024,
		   (uintmax_t) totalswap / 1024,
		   (uintmax_t) freeswap / 1024);
  else
    return Qnil;
#elif defined MSDOS
  unsigned long totalram, freeram, totalswap, freeswap;

  if (dos_memory_info (&totalram, &freeram, &totalswap, &freeswap) == 0)
    return list4i ((uintmax_t) totalram / 1024,
		   (uintmax_t) freeram / 1024,
		   (uintmax_t) totalswap / 1024,
		   (uintmax_t) freeswap / 1024);
  else
    return Qnil;
#else /* not HAVE_LINUX_SYSINFO, not WINDOWSNT, not MSDOS */
  /* FIXME: add more systems.  */
  return Qnil;
#endif /* HAVE_LINUX_SYSINFO, not WINDOWSNT, not MSDOS */
}