1 /* Get the system load averages.
3 Copyright (C) 1985, 1986, 1987, 1988, 1989, 1991, 1992, 1993, 1994,
4 1995, 1997, 1999, 2000, 2003, 2004, 2005 Free Software Foundation, Inc.
6 NOTE: The canonical source of this file is maintained with gnulib.
7 Bugs can be reported to bug-gnulib@gnu.org.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
12 any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
22 USA. */
24 /* Compile-time symbols that this file uses:
26 HAVE_PSTAT_GETDYNAMIC Define this if your system has the
27 pstat_getdynamic function. I think it
28 is unique to HPUX9. The best way to get the
29 definition is through the AC_FUNC_GETLOADAVG
30 macro that comes with autoconf 2.13 or newer.
31 If that isn't an option, then just put
32 AC_CHECK_FUNCS(pstat_getdynamic) in your
33 configure.in file.
34 FIXUP_KERNEL_SYMBOL_ADDR() Adjust address in returned struct nlist.
35 KERNEL_FILE Name of the kernel file to nlist.
36 LDAV_CVT() Scale the load average from the kernel.
37 Returns a double.
38 LDAV_SYMBOL Name of kernel symbol giving load average.
39 LOAD_AVE_TYPE Type of the load average array in the kernel.
40 Must be defined unless one of
41 apollo, DGUX, NeXT, or UMAX is defined;
42 or we have libkstat;
43 otherwise, no load average is available.
44 HAVE_NLIST_H nlist.h is available. NLIST_STRUCT defaults
45 to this.
46 NLIST_STRUCT Include nlist.h, not a.out.h, and
47 the nlist n_name element is a pointer,
48 not an array.
49 HAVE_STRUCT_NLIST_N_UN_N_NAME `n_un.n_name' is member of `struct nlist'.
50 LINUX_LDAV_FILE [__linux__, __CYGWIN__]: File containing
51 load averages.
53 Specific system predefines this file uses, aside from setting
54 default values if not emacs:
56 apollo
57 BSD Real BSD, not just BSD-like.
58 convex
59 DGUX
60 eunice UNIX emulator under VMS.
61 hpux
62 __MSDOS__ No-op for MSDOS.
63 NeXT
64 sgi
65 sequent Sequent Dynix 3.x.x (BSD)
66 _SEQUENT_ Sequent DYNIX/ptx 1.x.x (SYSV)
67 sony_news NEWS-OS (works at least for 4.1C)
68 UMAX
69 UMAX4_3
70 VMS
71 WINDOWS32 No-op for Windows95/NT.
72 __linux__ Linux: assumes /proc file system mounted.
73 Support from Michael K. Johnson.
74 __CYGWIN__ Cygwin emulates linux /proc/loadavg.
75 __NetBSD__ NetBSD: assumes /kern file system mounted.
77 In addition, to avoid nesting many #ifdefs, we internally set
78 LDAV_DONE to indicate that the load average has been computed.
80 We also #define LDAV_PRIVILEGED if a program will require
81 special installation to be able to call getloadavg. */
83 /* This should always be first. */
84 #ifdef HAVE_CONFIG_H
85 # include <config.h>
86 #endif
88 #include <errno.h>
89 #include <stdbool.h>
90 #include <stdio.h>
91 #include <stdlib.h>
93 /* Exclude all the code except the test program at the end
94 if the system has its own `getloadavg' function. */
96 #ifndef HAVE_GETLOADAVG
98 # include <sys/types.h>
100 /* Both the Emacs and non-Emacs sections want this. Some
101 configuration files' definitions for the LOAD_AVE_CVT macro (like
102 sparc.h's) use macros like FSCALE, defined here. */
103 # if defined (unix) || defined (__unix)
104 # include <sys/param.h>
105 # endif
107 # include "c-strtod.h"
108 # include "cloexec.h"
109 # include "intprops.h"
110 # include "xalloc.h"
112 /* The existing Emacs configuration files define a macro called
113 LOAD_AVE_CVT, which accepts a value of type LOAD_AVE_TYPE, and
114 returns the load average multiplied by 100. What we actually want
115 is a macro called LDAV_CVT, which returns the load average as an
116 unmultiplied double.
118 For backwards compatibility, we'll define LDAV_CVT in terms of
119 LOAD_AVE_CVT, but future machine config files should just define
120 LDAV_CVT directly. */
122 # if !defined (LDAV_CVT) && defined (LOAD_AVE_CVT)
123 # define LDAV_CVT(n) (LOAD_AVE_CVT (n) / 100.0)
124 # endif
126 # if !defined (BSD) && defined (ultrix)
127 /* Ultrix behaves like BSD on Vaxen. */
128 # define BSD
129 # endif
131 # ifdef NeXT
132 /* NeXT in the 2.{0,1,2} releases defines BSD in <sys/param.h>, which
133 conflicts with the definition understood in this file, that this
134 really is BSD. */
135 # undef BSD
137 /* NeXT defines FSCALE in <sys/param.h>. However, we take FSCALE being
138 defined to mean that the nlist method should be used, which is not true. */
139 # undef FSCALE
140 # endif
142 /* Same issues as for NeXT apply to the HURD-based GNU system. */
143 # ifdef __GNU__
144 # undef BSD
145 # undef FSCALE
146 # endif /* __GNU__ */
148 /* Set values that are different from the defaults, which are
149 set a little farther down with #ifndef. */
152 /* Some shorthands. */
154 # if defined (HPUX) && !defined (hpux)
155 # define hpux
156 # endif
158 # if defined (__hpux) && !defined (hpux)
159 # define hpux
160 # endif
162 # if defined (__sun) && !defined (sun)
163 # define sun
164 # endif
166 # if defined (hp300) && !defined (hpux)
167 # define MORE_BSD
168 # endif
170 # if defined (ultrix) && defined (mips)
171 # define decstation
172 # endif
174 # if defined (__SVR4) && !defined (SVR4)
175 # define SVR4
176 # endif
178 # if (defined (sun) && defined (SVR4)) || defined (SOLARIS2)
179 # define SUNOS_5
180 # endif
182 # if defined (__osf__) && (defined (__alpha) || defined (__alpha__))
183 # define OSF_ALPHA
184 # include <sys/mbuf.h>
185 # include <sys/socket.h>
186 # include <net/route.h>
187 # include <sys/table.h>
188 # endif
190 # if defined (__osf__) && (defined (mips) || defined (__mips__))
191 # define OSF_MIPS
192 # include <sys/table.h>
193 # endif
195 /* UTek's /bin/cc on the 4300 has no architecture specific cpp define by
196 default, but _MACH_IND_SYS_TYPES is defined in <sys/types.h>. Combine
197 that with a couple of other things and we'll have a unique match. */
198 # if !defined (tek4300) && defined (unix) && defined (m68k) && defined (mc68000) && defined (mc68020) && defined (_MACH_IND_SYS_TYPES)
199 # define tek4300 /* Define by emacs, but not by other users. */
200 # endif
203 /* VAX C can't handle multi-line #ifs, or lines longer than 256 chars. */
204 # ifndef LOAD_AVE_TYPE
206 # ifdef MORE_BSD
207 # define LOAD_AVE_TYPE long
208 # endif
210 # ifdef sun
211 # define LOAD_AVE_TYPE long
212 # endif
214 # ifdef decstation
215 # define LOAD_AVE_TYPE long
216 # endif
218 # ifdef _SEQUENT_
219 # define LOAD_AVE_TYPE long
220 # endif
222 # ifdef sgi
223 # define LOAD_AVE_TYPE long
224 # endif
226 # ifdef SVR4
227 # define LOAD_AVE_TYPE long
228 # endif
230 # ifdef sony_news
231 # define LOAD_AVE_TYPE long
232 # endif
234 # ifdef sequent
235 # define LOAD_AVE_TYPE long
236 # endif
238 # ifdef OSF_ALPHA
239 # define LOAD_AVE_TYPE long
240 # endif
242 # if defined (ardent) && defined (titan)
243 # define LOAD_AVE_TYPE long
244 # endif
246 # ifdef tek4300
247 # define LOAD_AVE_TYPE long
248 # endif
250 # if defined (alliant) && defined (i860) /* Alliant FX/2800 */
251 # define LOAD_AVE_TYPE long
252 # endif
254 # ifdef _AIX
255 # define LOAD_AVE_TYPE long
256 # endif
258 # ifdef convex
259 # define LOAD_AVE_TYPE double
260 # ifndef LDAV_CVT
261 # define LDAV_CVT(n) (n)
262 # endif
263 # endif
265 # endif /* No LOAD_AVE_TYPE. */
267 # ifdef OSF_ALPHA
268 /* <sys/param.h> defines an incorrect value for FSCALE on Alpha OSF/1,
269 according to ghazi@noc.rutgers.edu. */
270 # undef FSCALE
271 # define FSCALE 1024.0
272 # endif
274 # if defined (alliant) && defined (i860) /* Alliant FX/2800 */
275 /* <sys/param.h> defines an incorrect value for FSCALE on an
276 Alliant FX/2800 Concentrix 2.2, according to ghazi@noc.rutgers.edu. */
277 # undef FSCALE
278 # define FSCALE 100.0
279 # endif
282 # ifndef FSCALE
284 /* SunOS and some others define FSCALE in sys/param.h. */
286 # ifdef MORE_BSD
287 # define FSCALE 2048.0
288 # endif
290 # if defined (MIPS) || defined (SVR4) || defined (decstation)
291 # define FSCALE 256
292 # endif
294 # if defined (sgi) || defined (sequent)
295 /* Sometimes both MIPS and sgi are defined, so FSCALE was just defined
296 above under #ifdef MIPS. But we want the sgi value. */
297 # undef FSCALE
298 # define FSCALE 1000.0
299 # endif
301 # if defined (ardent) && defined (titan)
302 # define FSCALE 65536.0
303 # endif
305 # ifdef tek4300
306 # define FSCALE 100.0
307 # endif
309 # ifdef _AIX
310 # define FSCALE 65536.0
311 # endif
313 # endif /* Not FSCALE. */
315 # if !defined (LDAV_CVT) && defined (FSCALE)
316 # define LDAV_CVT(n) (((double) (n)) / FSCALE)
317 # endif
319 # ifndef NLIST_STRUCT
320 # if HAVE_NLIST_H
321 # define NLIST_STRUCT
322 # endif
323 # endif
325 # if defined (sgi) || (defined (mips) && !defined (BSD))
326 # define FIXUP_KERNEL_SYMBOL_ADDR(nl) ((nl)[0].n_value &= ~(1 << 31))
327 # endif
330 # if !defined (KERNEL_FILE) && defined (sequent)
331 # define KERNEL_FILE "/dynix"
332 # endif
334 # if !defined (KERNEL_FILE) && defined (hpux)
335 # define KERNEL_FILE "/hp-ux"
336 # endif
338 # if !defined (KERNEL_FILE) && (defined (_SEQUENT_) || defined (MIPS) || defined (SVR4) || defined (ISC) || defined (sgi) || (defined (ardent) && defined (titan)))
339 # define KERNEL_FILE "/unix"
340 # endif
343 # if !defined (LDAV_SYMBOL) && defined (alliant)
344 # define LDAV_SYMBOL "_Loadavg"
345 # endif
347 # if !defined (LDAV_SYMBOL) && ((defined (hpux) && !defined (hp9000s300)) || defined (_SEQUENT_) || defined (SVR4) || defined (ISC) || defined (sgi) || (defined (ardent) && defined (titan)) || defined (_AIX))
348 # define LDAV_SYMBOL "avenrun"
349 # endif
351 # include <unistd.h>
353 /* LOAD_AVE_TYPE should only get defined if we're going to use the
354 nlist method. */
355 # if !defined (LOAD_AVE_TYPE) && (defined (BSD) || defined (LDAV_CVT) || defined (KERNEL_FILE) || defined (LDAV_SYMBOL))
356 # define LOAD_AVE_TYPE double
357 # endif
359 # ifdef LOAD_AVE_TYPE
361 # ifndef VMS
362 # ifndef __linux__
363 # ifndef NLIST_STRUCT
364 # include <a.out.h>
365 # else /* NLIST_STRUCT */
366 # include <nlist.h>
367 # endif /* NLIST_STRUCT */
369 # ifdef SUNOS_5
370 # include <fcntl.h>
371 # include <kvm.h>
372 # include <kstat.h>
373 # endif
375 # if defined (hpux) && defined (HAVE_PSTAT_GETDYNAMIC)
376 # include <sys/pstat.h>
377 # endif
379 # ifndef KERNEL_FILE
380 # define KERNEL_FILE "/vmunix"
381 # endif /* KERNEL_FILE */
383 # ifndef LDAV_SYMBOL
384 # define LDAV_SYMBOL "_avenrun"
385 # endif /* LDAV_SYMBOL */
386 # endif /* __linux__ */
388 # else /* VMS */
390 # ifndef eunice
391 # include <iodef.h>
392 # include <descrip.h>
393 # else /* eunice */
394 # include <vms/iodef.h>
395 # endif /* eunice */
396 # endif /* VMS */
398 # ifndef LDAV_CVT
399 # define LDAV_CVT(n) ((double) (n))
400 # endif /* !LDAV_CVT */
402 # endif /* LOAD_AVE_TYPE */
404 # if defined (__GNU__) && !defined (NeXT)
405 /* Note that NeXT Openstep defines __GNU__ even though it should not. */
406 /* GNU system acts much like NeXT, for load average purposes,
407 but not exactly. */
408 # define NeXT
409 # define host_self mach_host_self
410 # endif
412 # ifdef NeXT
413 # ifdef HAVE_MACH_MACH_H
414 # include <mach/mach.h>
415 # else
416 # include <mach.h>
417 # endif
418 # endif /* NeXT */
420 # ifdef sgi
421 # include <sys/sysmp.h>
422 # endif /* sgi */
424 # ifdef UMAX
425 # include <signal.h>
426 # include <sys/time.h>
427 # include <sys/wait.h>
428 # include <sys/syscall.h>
430 # ifdef UMAX_43
431 # include <machine/cpu.h>
432 # include <inq_stats/statistics.h>
433 # include <inq_stats/sysstats.h>
434 # include <inq_stats/cpustats.h>
435 # include <inq_stats/procstats.h>
436 # else /* Not UMAX_43. */
437 # include <sys/sysdefs.h>
438 # include <sys/statistics.h>
439 # include <sys/sysstats.h>
440 # include <sys/cpudefs.h>
441 # include <sys/cpustats.h>
442 # include <sys/procstats.h>
443 # endif /* Not UMAX_43. */
444 # endif /* UMAX */
446 # ifdef DGUX
447 # include <sys/dg_sys_info.h>
448 # endif
450 # include "fcntl--.h"
451 \f
452 /* Avoid static vars inside a function since in HPUX they dump as pure. */
454 # ifdef NeXT
455 static processor_set_t default_set;
456 static bool getloadavg_initialized;
457 # endif /* NeXT */
459 # ifdef UMAX
460 static unsigned int cpus = 0;
461 static unsigned int samples;
462 # endif /* UMAX */
464 # ifdef DGUX
465 static struct dg_sys_info_load_info load_info; /* what-a-mouthful! */
466 # endif /* DGUX */
468 # if !defined (HAVE_LIBKSTAT) && defined (LOAD_AVE_TYPE)
469 /* File descriptor open to /dev/kmem or VMS load ave driver. */
470 static int channel;
471 /* True iff channel is valid. */
472 static bool getloadavg_initialized;
473 /* Offset in kmem to seek to read load average, or 0 means invalid. */
474 static long offset;
476 # if !defined (VMS) && !defined (sgi) && !defined (__linux__)
477 static struct nlist nl[2];
478 # endif /* Not VMS or sgi */
480 # ifdef SUNOS_5
481 static kvm_t *kd;
482 # endif /* SUNOS_5 */
484 # endif /* LOAD_AVE_TYPE && !HAVE_LIBKSTAT */
485 \f
486 /* Put the 1 minute, 5 minute and 15 minute load averages
487 into the first NELEM elements of LOADAVG.
488 Return the number written (never more than 3, but may be less than NELEM),
489 or -1 if an error occurred. */
491 int
492 getloadavg (double loadavg[], int nelem)
493 {
494 int elem = 0; /* Return value. */
496 # ifdef NO_GET_LOAD_AVG
497 # define LDAV_DONE
498 /* Set errno to zero to indicate that there was no particular error;
499 this function just can't work at all on this system. */
500 errno = 0;
501 elem = -1;
502 # endif
504 # if !defined (LDAV_DONE) && defined (HAVE_LIBKSTAT)
505 /* Use libkstat because we don't have to be root. */
506 # define LDAV_DONE
507 kstat_ctl_t *kc;
508 kstat_t *ksp;
509 kstat_named_t *kn;
511 kc = kstat_open ();
512 if (kc == 0)
513 return -1;
514 ksp = kstat_lookup (kc, "unix", 0, "system_misc");
515 if (ksp == 0)
516 return -1;
517 if (kstat_read (kc, ksp, 0) == -1)
518 return -1;
521 kn = kstat_data_lookup (ksp, "avenrun_1min");
522 if (kn == 0)
523 {
524 /* Return -1 if no load average information is available. */
525 nelem = 0;
526 elem = -1;
527 }
529 if (nelem >= 1)
530 loadavg[elem++] = (double) kn->value.ul / FSCALE;
532 if (nelem >= 2)
533 {
534 kn = kstat_data_lookup (ksp, "avenrun_5min");
535 if (kn != 0)
536 {
537 loadavg[elem++] = (double) kn->value.ul / FSCALE;
539 if (nelem >= 3)
540 {
541 kn = kstat_data_lookup (ksp, "avenrun_15min");
542 if (kn != 0)
543 loadavg[elem++] = (double) kn->value.ul / FSCALE;
544 }
545 }
546 }
548 kstat_close (kc);
549 # endif /* HAVE_LIBKSTAT */
551 # if !defined (LDAV_DONE) && defined (hpux) && defined (HAVE_PSTAT_GETDYNAMIC)
552 /* Use pstat_getdynamic() because we don't have to be root. */
553 # define LDAV_DONE
554 # undef LOAD_AVE_TYPE
556 struct pst_dynamic dyn_info;
557 if (pstat_getdynamic (&dyn_info, sizeof (dyn_info), 0, 0) < 0)
558 return -1;
559 if (nelem > 0)
560 loadavg[elem++] = dyn_info.psd_avg_1_min;
561 if (nelem > 1)
562 loadavg[elem++] = dyn_info.psd_avg_5_min;
563 if (nelem > 2)
564 loadavg[elem++] = dyn_info.psd_avg_15_min;
566 # endif /* hpux && HAVE_PSTAT_GETDYNAMIC */
568 # if !defined (LDAV_DONE) && (defined (__linux__) || defined (__CYGWIN__))
569 # define LDAV_DONE
570 # undef LOAD_AVE_TYPE
572 # ifndef LINUX_LDAV_FILE
573 # define LINUX_LDAV_FILE "/proc/loadavg"
574 # endif
576 char ldavgbuf[3 * (INT_STRLEN_BOUND (int) + sizeof ".00 ")];
577 char const *ptr = ldavgbuf;
578 int fd, count;
580 fd = open (LINUX_LDAV_FILE, O_RDONLY);
581 if (fd == -1)
582 return -1;
583 count = read (fd, ldavgbuf, sizeof ldavgbuf - 1);
584 (void) close (fd);
585 if (count <= 0)
586 return -1;
587 ldavgbuf[count] = '\0';
589 for (elem = 0; elem < nelem; elem++)
590 {
591 char *endptr;
592 double d = c_strtod (ptr, &endptr);
593 if (ptr == endptr)
594 {
595 if (elem == 0)
596 return -1;
597 break;
598 }
599 loadavg[elem] = d;
600 ptr = endptr;
601 }
603 return elem;
605 # endif /* __linux__ || __CYGWIN__ */
607 # if !defined (LDAV_DONE) && defined (__NetBSD__)
608 # define LDAV_DONE
609 # undef LOAD_AVE_TYPE
611 # ifndef NETBSD_LDAV_FILE
612 # define NETBSD_LDAV_FILE "/kern/loadavg"
613 # endif
615 unsigned long int load_ave[3], scale;
616 int count;
617 FILE *fp;
619 fp = fopen (NETBSD_LDAV_FILE, "r");
620 if (fp == NULL)
621 return -1;
622 count = fscanf (fp, "%lu %lu %lu %lu\n",
623 &load_ave[0], &load_ave[1], &load_ave[2],
624 &scale);
625 (void) fclose (fp);
626 if (count != 4)
627 return -1;
629 for (elem = 0; elem < nelem; elem++)
630 loadavg[elem] = (double) load_ave[elem] / (double) scale;
632 return elem;
634 # endif /* __NetBSD__ */
636 # if !defined (LDAV_DONE) && defined (NeXT)
637 # define LDAV_DONE
638 /* The NeXT code was adapted from iscreen 3.2. */
640 host_t host;
641 struct processor_set_basic_info info;
642 unsigned int info_count;
644 /* We only know how to get the 1-minute average for this system,
645 so even if the caller asks for more than 1, we only return 1. */
647 if (!getloadavg_initialized)
648 {
649 if (processor_set_default (host_self (), &default_set) == KERN_SUCCESS)
650 getloadavg_initialized = true;
651 }
653 if (getloadavg_initialized)
654 {
655 info_count = PROCESSOR_SET_BASIC_INFO_COUNT;
656 if (processor_set_info (default_set, PROCESSOR_SET_BASIC_INFO, &host,
657 (processor_set_info_t) &info, &info_count)
658 != KERN_SUCCESS)
659 getloadavg_initialized = false;
660 else
661 {
662 if (nelem > 0)
663 loadavg[elem++] = (double) info.load_average / LOAD_SCALE;
664 }
665 }
667 if (!getloadavg_initialized)
668 return -1;
669 # endif /* NeXT */
671 # if !defined (LDAV_DONE) && defined (UMAX)
672 # define LDAV_DONE
673 /* UMAX 4.2, which runs on the Encore Multimax multiprocessor, does not
674 have a /dev/kmem. Information about the workings of the running kernel
675 can be gathered with inq_stats system calls.
676 We only know how to get the 1-minute average for this system. */
678 struct proc_summary proc_sum_data;
679 struct stat_descr proc_info;
680 double load;
681 register unsigned int i, j;
683 if (cpus == 0)
684 {
685 register unsigned int c, i;
686 struct cpu_config conf;
687 struct stat_descr desc;
689 desc.sd_next = 0;
690 desc.sd_subsys = SUBSYS_CPU;
691 desc.sd_type = CPUTYPE_CONFIG;
692 desc.sd_addr = (char *) &conf;
693 desc.sd_size = sizeof conf;
695 if (inq_stats (1, &desc))
696 return -1;
698 c = 0;
699 for (i = 0; i < conf.config_maxclass; ++i)
700 {
701 struct class_stats stats;
702 bzero ((char *) &stats, sizeof stats);
704 desc.sd_type = CPUTYPE_CLASS;
705 desc.sd_objid = i;
706 desc.sd_addr = (char *) &stats;
707 desc.sd_size = sizeof stats;
709 if (inq_stats (1, &desc))
710 return -1;
712 c += stats.class_numcpus;
713 }
714 cpus = c;
715 samples = cpus < 2 ? 3 : (2 * cpus / 3);
716 }
718 proc_info.sd_next = 0;
719 proc_info.sd_subsys = SUBSYS_PROC;
720 proc_info.sd_type = PROCTYPE_SUMMARY;
721 proc_info.sd_addr = (char *) &proc_sum_data;
722 proc_info.sd_size = sizeof (struct proc_summary);
723 proc_info.sd_sizeused = 0;
725 if (inq_stats (1, &proc_info) != 0)
726 return -1;
728 load = proc_sum_data.ps_nrunnable;
729 j = 0;
730 for (i = samples - 1; i > 0; --i)
731 {
732 load += proc_sum_data.ps_nrun[j];
733 if (j++ == PS_NRUNSIZE)
734 j = 0;
735 }
737 if (nelem > 0)
738 loadavg[elem++] = load / samples / cpus;
739 # endif /* UMAX */
741 # if !defined (LDAV_DONE) && defined (DGUX)
742 # define LDAV_DONE
743 /* This call can return -1 for an error, but with good args
744 it's not supposed to fail. The first argument is for no
745 apparent reason of type `long int *'. */
746 dg_sys_info ((long int *) &load_info,
747 DG_SYS_INFO_LOAD_INFO_TYPE,
748 DG_SYS_INFO_LOAD_VERSION_0);
750 if (nelem > 0)
751 loadavg[elem++] = load_info.one_minute;
752 if (nelem > 1)
753 loadavg[elem++] = load_info.five_minute;
754 if (nelem > 2)
755 loadavg[elem++] = load_info.fifteen_minute;
756 # endif /* DGUX */
758 # if !defined (LDAV_DONE) && defined (apollo)
759 # define LDAV_DONE
760 /* Apollo code from lisch@mentorg.com (Ray Lischner).
762 This system call is not documented. The load average is obtained as
763 three long integers, for the load average over the past minute,
764 five minutes, and fifteen minutes. Each value is a scaled integer,
765 with 16 bits of integer part and 16 bits of fraction part.
767 I'm not sure which operating system first supported this system call,
768 but I know that SR10.2 supports it. */
770 extern void proc1_$get_loadav ();
771 unsigned long load_ave[3];
773 proc1_$get_loadav (load_ave);
775 if (nelem > 0)
776 loadavg[elem++] = load_ave[0] / 65536.0;
777 if (nelem > 1)
778 loadavg[elem++] = load_ave[1] / 65536.0;
779 if (nelem > 2)
780 loadavg[elem++] = load_ave[2] / 65536.0;
781 # endif /* apollo */
783 # if !defined (LDAV_DONE) && defined (OSF_MIPS)
784 # define LDAV_DONE
786 struct tbl_loadavg load_ave;
787 table (TBL_LOADAVG, 0, &load_ave, 1, sizeof (load_ave));
788 loadavg[elem++]
789 = (load_ave.tl_lscale == 0
790 ? load_ave.tl_avenrun.d[0]
791 : (load_ave.tl_avenrun.l[0] / (double) load_ave.tl_lscale));
792 # endif /* OSF_MIPS */
794 # if !defined (LDAV_DONE) && (defined (__MSDOS__) || defined (WINDOWS32))
795 # define LDAV_DONE
797 /* A faithful emulation is going to have to be saved for a rainy day. */
798 for ( ; elem < nelem; elem++)
799 {
800 loadavg[elem] = 0.0;
801 }
802 # endif /* __MSDOS__ || WINDOWS32 */
804 # if !defined (LDAV_DONE) && defined (OSF_ALPHA)
805 # define LDAV_DONE
807 struct tbl_loadavg load_ave;
808 table (TBL_LOADAVG, 0, &load_ave, 1, sizeof (load_ave));
809 for (elem = 0; elem < nelem; elem++)
810 loadavg[elem]
811 = (load_ave.tl_lscale == 0
812 ? load_ave.tl_avenrun.d[elem]
813 : (load_ave.tl_avenrun.l[elem] / (double) load_ave.tl_lscale));
814 # endif /* OSF_ALPHA */
816 # if !defined (LDAV_DONE) && defined (VMS)
817 /* VMS specific code -- read from the Load Ave driver. */
819 LOAD_AVE_TYPE load_ave[3];
820 static bool getloadavg_initialized;
821 # ifdef eunice
822 struct
823 {
824 int dsc$w_length;
825 char *dsc$a_pointer;
826 } descriptor;
827 # endif
829 /* Ensure that there is a channel open to the load ave device. */
830 if (!getloadavg_initialized)
831 {
832 /* Attempt to open the channel. */
833 # ifdef eunice
834 descriptor.dsc$w_length = 18;
835 descriptor.dsc$a_pointer = "$$VMS_LOAD_AVERAGE";
836 # else
837 $DESCRIPTOR (descriptor, "LAV0:");
838 # endif
839 if (sys$assign (&descriptor, &channel, 0, 0) & 1)
840 getloadavg_initialized = true;
841 }
843 /* Read the load average vector. */
844 if (getloadavg_initialized
845 && !(sys$qiow (0, channel, IO$_READVBLK, 0, 0, 0,
846 load_ave, 12, 0, 0, 0, 0) & 1))
847 {
848 sys$dassgn (channel);
849 getloadavg_initialized = false;
850 }
852 if (!getloadavg_initialized)
853 return -1;
854 # endif /* VMS */
856 # if !defined (LDAV_DONE) && defined (LOAD_AVE_TYPE) && !defined (VMS)
858 /* UNIX-specific code -- read the average from /dev/kmem. */
860 # define LDAV_PRIVILEGED /* This code requires special installation. */
862 LOAD_AVE_TYPE load_ave[3];
864 /* Get the address of LDAV_SYMBOL. */
865 if (offset == 0)
866 {
867 # ifndef sgi
868 # ifndef NLIST_STRUCT
869 strcpy (nl[0].n_name, LDAV_SYMBOL);
870 strcpy (nl[1].n_name, "");
871 # else /* NLIST_STRUCT */
872 # ifdef HAVE_STRUCT_NLIST_N_UN_N_NAME
873 nl[0].n_un.n_name = LDAV_SYMBOL;
874 nl[1].n_un.n_name = 0;
875 # else /* not HAVE_STRUCT_NLIST_N_UN_N_NAME */
876 nl[0].n_name = LDAV_SYMBOL;
877 nl[1].n_name = 0;
878 # endif /* not HAVE_STRUCT_NLIST_N_UN_N_NAME */
879 # endif /* NLIST_STRUCT */
881 # ifndef SUNOS_5
882 if (
883 # if !(defined (_AIX) && !defined (ps2))
884 nlist (KERNEL_FILE, nl)
885 # else /* _AIX */
886 knlist (nl, 1, sizeof (nl[0]))
887 # endif
888 >= 0)
889 /* Omit "&& nl[0].n_type != 0 " -- it breaks on Sun386i. */
890 {
891 # ifdef FIXUP_KERNEL_SYMBOL_ADDR
892 FIXUP_KERNEL_SYMBOL_ADDR (nl);
893 # endif
894 offset = nl[0].n_value;
895 }
896 # endif /* !SUNOS_5 */
897 # else /* sgi */
898 int ldav_off;
900 ldav_off = sysmp (MP_KERNADDR, MPKA_AVENRUN);
901 if (ldav_off != -1)
902 offset = (long int) ldav_off & 0x7fffffff;
903 # endif /* sgi */
904 }
906 /* Make sure we have /dev/kmem open. */
907 if (!getloadavg_initialized)
908 {
909 # ifndef SUNOS_5
910 channel = open ("/dev/kmem", O_RDONLY);
911 if (channel >= 0)
912 {
913 /* Set the channel to close on exec, so it does not
914 litter any child's descriptor table. */
915 set_cloexec_flag (channel, true);
916 getloadavg_initialized = true;
917 }
918 # else /* SUNOS_5 */
919 /* We pass 0 for the kernel, corefile, and swapfile names
920 to use the currently running kernel. */
921 kd = kvm_open (0, 0, 0, O_RDONLY, 0);
922 if (kd != 0)
923 {
924 /* nlist the currently running kernel. */
925 kvm_nlist (kd, nl);
926 offset = nl[0].n_value;
927 getloadavg_initialized = true;
928 }
929 # endif /* SUNOS_5 */
930 }
932 /* If we can, get the load average values. */
933 if (offset && getloadavg_initialized)
934 {
935 /* Try to read the load. */
936 # ifndef SUNOS_5
937 if (lseek (channel, offset, 0) == -1L
938 || read (channel, (char *) load_ave, sizeof (load_ave))
939 != sizeof (load_ave))
940 {
941 close (channel);
942 getloadavg_initialized = false;
943 }
944 # else /* SUNOS_5 */
945 if (kvm_read (kd, offset, (char *) load_ave, sizeof (load_ave))
946 != sizeof (load_ave))
947 {
948 kvm_close (kd);
949 getloadavg_initialized = false;
950 }
951 # endif /* SUNOS_5 */
952 }
954 if (offset == 0 || !getloadavg_initialized)
955 return -1;
956 # endif /* LOAD_AVE_TYPE and not VMS */
958 # if !defined (LDAV_DONE) && defined (LOAD_AVE_TYPE) /* Including VMS. */
959 if (nelem > 0)
960 loadavg[elem++] = LDAV_CVT (load_ave[0]);
961 if (nelem > 1)
962 loadavg[elem++] = LDAV_CVT (load_ave[1]);
963 if (nelem > 2)
964 loadavg[elem++] = LDAV_CVT (load_ave[2]);
966 # define LDAV_DONE
967 # endif /* !LDAV_DONE && LOAD_AVE_TYPE */
969 # if !defined LDAV_DONE
970 /* Set errno to zero to indicate that there was no particular error;
971 this function just can't work at all on this system. */
972 errno = 0;
973 elem = -1;
974 # endif
975 return elem;
976 }
978 #endif /* ! HAVE_GETLOADAVG */
979 \f
980 #ifdef TEST
981 int
982 main (int argc, char **argv)
983 {
984 int naptime = 0;
986 if (argc > 1)
987 naptime = atoi (argv[1]);
989 while (1)
990 {
991 double avg[3];
992 int loads;
994 errno = 0; /* Don't be misled if it doesn't set errno. */
995 loads = getloadavg (avg, 3);
996 if (loads == -1)
997 {
998 perror ("Error getting load average");
999 return EXIT_FAILURE;
1000 }
1001 if (loads > 0)
1002 printf ("1-minute: %f ", avg[0]);
1003 if (loads > 1)
1004 printf ("5-minute: %f ", avg[1]);
1005 if (loads > 2)
1006 printf ("15-minute: %f ", avg[2]);
1007 if (loads > 0)
1008 putchar ('\n');
1010 if (naptime == 0)
1011 break;
1012 sleep (naptime);
1013 }
1015 return EXIT_SUCCESS;
1016 }
1017 #endif /* TEST */