src/OS/os.c-Linux-libc5

   1 /* $Cambridge: exim/src/OS/os.c-Linux-libc5,v 1.1 2004/10/06 15:07:39 ph10 Exp $ */
   2
   3 /*************************************************
   4 *     Exim - an Internet mail transport agent    *
   5 *************************************************/
   6
   7 /* Copyright (c) University of Cambridge 2001 */
   8 /* See the file NOTICE for conditions of use and distribution. */
   9
  10 /* Linux-specific code. This is concatenated onto the generic src/os.c file.
  11 Linux has an apparently unique way of getting the load average, so we provide a
  12 unique function here, and define OS_LOAD_AVERAGE to stop src/os.c trying to
  13 provide the function. The macro may be set initially anyway, when compiling os.
  14 for utilities that don't want this function. */
  15
  16 #ifndef OS_LOAD_AVERAGE
  17 #define OS_LOAD_AVERAGE
  18
  19 int
  20 os_getloadavg(void)
  21 {
  22 char buffer[40];
  23 double avg;
  24 int count;
  25 int fd = open ("/proc/loadavg", O_RDONLY);
  26 if (fd == -1) return -1;
  27 count = read (fd, buffer, sizeof(buffer));
  28 (void)close (fd);
  29 if (count <= 0) return -1;
  30 count = sscanf (buffer, "%lf", &avg);
  31 if (count < 1) return -1;
  32
  33 return (int)(avg * 1000.0);
  34 }
  35
  36 #endif  /* OS_LOAD_AVERAGE */
  37
  38 /* End of os.c-Linux */
  39