1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
6 /* See the file NOTICE for conditions of use and distribution. */
16 # define US (unsigned char *)
19 /* This source file contains "default" system-dependent functions which
20 provide functionality (or lack of it) in cases where the OS-specific os.c
21 file has not. Some of them are tailored by macros defined in os.h files. */
24 #ifndef OS_RESTARTING_SIGNAL
25 /*************************************************
26 * Set up restarting signal *
27 *************************************************/
29 /* This function has the same functionality as the ANSI C signal() function,
30 except that it arranges that, if the signal happens during a system call, the
31 system call gets restarted. (Also, it doesn't return a result.) Different
32 versions of Unix have different defaults, and different ways of setting up a
33 restarting signal handler. If the functionality is not available, the signal
34 should be set to be ignored. This function is used only for catching SIGUSR1.
38 os_restarting_signal(int sig, void (*handler)(int))
40 /* Many systems have the SA_RESTART sigaction for specifying that a signal
41 should restart system calls. These include SunOS5, AIX, BSDI, IRIX, FreeBSD,
42 OSF1, Linux and HP-UX 10 (but *not* HP-UX 9). */
46 act.sa_handler = handler;
47 sigemptyset(&(act.sa_mask));
48 act.sa_flags = SA_RESTART;
49 sigaction(sig, &act, NULL);
52 printf("Used SA_RESTART\n");
55 /* SunOS4 and Ultrix default to non-interruptable signals, with SV_INTERRUPT
56 for making them interruptable. This seems to be a dying fashion. */
58 #elif defined SV_INTERRUPT
62 printf("Used default signal()\n");
66 /* If neither SA_RESTART nor SV_INTERRUPT is available we don't know how to
67 set up a restarting signal, so simply suppress the facility. */
73 printf("Used SIG_IGN\n");
79 #endif /* OS_RESTARTING_SIGNAL */
82 #ifndef OS_NON_RESTARTING_SIGNAL
83 /*************************************************
84 * Set up non-restarting signal *
85 *************************************************/
87 /* This function has the same functionality as the ANSI C signal() function,
88 except that it arranges that, if the signal happens during a system call, the
89 system call gets interrupted. (Also, it doesn't return a result.) Different
90 versions of Unix have different defaults, and different ways of setting up a
91 non-restarting signal handler. For systems for which we don't know what to do,
92 just use the normal signal() function and hope for the best. */
95 os_non_restarting_signal(int sig, void (*handler)(int))
97 /* Many systems have the SA_RESTART sigaction for specifying that a signal
98 should restart system calls. These include SunOS5, AIX, BSDI, IRIX, FreeBSD,
99 OSF1, Linux and HP-UX 10 (but *not* HP-UX 9). */
102 struct sigaction act;
103 act.sa_handler = handler;
104 sigemptyset(&(act.sa_mask));
106 sigaction(sig, &act, NULL);
109 printf("Used sigaction() with flags = 0\n");
112 /* SunOS4 and Ultrix default to non-interruptable signals, with SV_INTERRUPT
113 for making them interruptable. This seems to be a dying fashion. */
115 #elif defined SV_INTERRUPT
117 sv.sv_handler = handler;
118 sv.sv_flags = SV_INTERRUPT;
120 sigvec(sig, &sv, NULL);
123 printf("Used sigvec() with flags = SV_INTERRUPT\n");
126 /* If neither SA_RESTART nor SV_INTERRUPT is available we don't know how to
127 set up a restarting signal, so just use the standard signal() function. */
130 signal(sig, handler);
133 printf("Used default signal()\n");
139 #endif /* OS_NON_RESTARTING_SIGNAL */
143 #ifdef STRERROR_FROM_ERRLIST
144 /*************************************************
145 * Provide strerror() for non-ANSI libraries *
146 *************************************************/
148 /* Some old-fashioned systems still around (e.g. SunOS4) don't have strerror()
149 in their libraries, but can provide the same facility by this simple
150 alternative function. */
155 if (n < 0 || n >= sys_nerr) return "unknown error number";
156 return sys_errlist[n];
158 #endif /* STRERROR_FROM_ERRLIST */
163 /*************************************************
164 * Provide strsignal() for systems without *
165 *************************************************/
167 /* Some systems have strsignal() to turn signal numbers into names; others
168 may have other means of doing this. This function is used for those systems
169 that have nothing. It provides a basic translation for the common standard
170 signal numbers. I've been extra cautious with the ifdef's here. Probably more
171 than is necessary... */
174 os_strsignal(const int n)
179 case SIGHUP: return "hangup";
183 case SIGINT: return "interrupt";
187 case SIGQUIT: return "quit";
191 case SIGILL: return "illegal instruction";
195 case SIGTRAP: return "trace trap";
199 case SIGABRT: return "abort";
203 case SIGEMT: return "EMT instruction";
207 case SIGFPE: return "arithmetic exception";
211 case SIGKILL: return "killed";
215 case SIGBUS: return "bus error";
219 case SIGSEGV: return "segmentation fault";
223 case SIGSYS: return "bad system call";
227 case SIGPIPE: return "broken pipe";
231 case SIGALRM: return "alarm";
235 case SIGTERM: return "terminated";
239 case SIGUSR1: return "user signal 1";
243 case SIGUSR2: return "user signal 2";
247 case SIGCHLD: return "child stop or exit";
251 case SIGPWR: return "power fail/restart";
255 case SIGURG: return "urgent condition on I/O channel";
259 case SIGSTOP: return "stop";
263 case SIGTSTP: return "stop from tty";
267 case SIGXCPU: return "exceeded CPU limit";
271 case SIGXFSZ: return "exceeded file size limit";
274 default: return "unrecognized signal number";
277 #endif /* OS_STRSIGNAL */
282 /*************************************************
283 * Provide strexit() for systems without *
284 *************************************************/
286 /* Actually, I don't know of any system that has a strexit() function to turn
287 exit codes into text, but this function is implemented this way so that if any
288 OS does have such a thing, it could be used instead of this build-in one. */
291 os_strexit(const int n)
295 /* On systems without sysexits.h we can assume only those exit codes
296 that are given a default value in exim.h. */
299 case EX_USAGE: return "(could mean usage or syntax error)";
300 case EX_DATAERR: return "(could mean error in input data)";
301 case EX_NOINPUT: return "(could mean input data missing)";
302 case EX_NOUSER: return "(could mean user nonexistent)";
303 case EX_NOHOST: return "(could mean host nonexistent)";
304 case EX_SOFTWARE: return "(could mean internal software error)";
305 case EX_OSERR: return "(could mean internal operating system error)";
306 case EX_OSFILE: return "(could mean system file missing)";
307 case EX_IOERR: return "(could mean input/output error)";
308 case EX_PROTOCOL: return "(could mean protocol error)";
309 case EX_NOPERM: return "(could mean permission denied)";
312 case EX_EXECFAILED: return "(could mean unable to exec or command does not exist)";
313 case EX_UNAVAILABLE: return "(could mean service or program unavailable)";
314 case EX_CANTCREAT: return "(could mean can't create output file)";
315 case EX_TEMPFAIL: return "(could mean temporary error)";
316 case EX_CONFIG: return "(could mean configuration error)";
320 #endif /* OS_STREXIT */
325 /***********************************************************
326 * Load average function *
327 ***********************************************************/
329 /* Although every Unix seems to have a different way of getting the load
330 average, a number of them have things in common. Some common variants are
331 provided below, but if an OS has unique requirements it can be handled in
332 a specific os.c file. What is required is a function called os_getloadavg
333 which takes no arguments and passes back the load average * 1000 as an int,
334 or -1 if no data is available. */
337 /* ----------------------------------------------------------------------- */
338 /* If the OS has got a BSD getloadavg() function, life is very easy. */
340 #if !defined(OS_LOAD_AVERAGE) && defined(HAVE_BSD_GETLOADAVG)
341 #define OS_LOAD_AVERAGE
347 int loads = getloadavg (&avg, 1);
348 if (loads != 1) return -1;
349 return (int)(avg * 1000.0);
352 /* ----------------------------------------------------------------------- */
356 /* ----------------------------------------------------------------------- */
357 /* Only SunOS5 has the kstat functions as far as I know, but put the code
358 here as there is the -hal variant, and other systems might follow this road one
361 #if !defined(OS_LOAD_AVERAGE) && defined(HAVE_KSTAT)
362 #define OS_LOAD_AVERAGE
374 if ((kc = kstat_open()) == NULL ||
375 (ksp = kstat_lookup(kc, LOAD_AVG_KSTAT_MODULE, 0, LOAD_AVG_KSTAT))
377 kstat_read(kc, ksp, NULL) < 0 ||
378 (kn = kstat_data_lookup(ksp, LOAD_AVG_SYMBOL)) == NULL)
381 avg = (int)(((double)(kn->LOAD_AVG_FIELD)/FSCALE) * 1000.0);
388 /* ----------------------------------------------------------------------- */
392 /* ----------------------------------------------------------------------- */
393 /* Handle OS where a kernel symbol has to be read from /dev/kmem */
395 #if !defined(OS_LOAD_AVERAGE) && defined(HAVE_DEV_KMEM)
396 #define OS_LOAD_AVERAGE
400 static int avg_kd = -1;
401 static long avg_offset;
411 nl[0].n_name = LOAD_AVG_SYMBOL;
413 nlist (KERNEL_PATH, nl);
414 avg_offset = (long)nl[0].n_value;
415 avg_kd = open ("/dev/kmem", 0);
416 if (avg_kd < 0) return -1;
417 (void) fcntl(avg_kd, F_SETFD, FD_CLOEXEC);
420 if (lseek (avg_kd, avg_offset, 0) == -1L
421 || read (avg_kd, CS (&avg), sizeof (avg)) != sizeof(avg))
424 return (int)(((double)avg/FSCALE)*1000.0);
428 /* ----------------------------------------------------------------------- */
432 /* ----------------------------------------------------------------------- */
433 /* If nothing is known about this OS, then the load average facility is
436 #ifndef OS_LOAD_AVERAGE
446 /* ----------------------------------------------------------------------- */
450 #if !defined FIND_RUNNING_INTERFACES
451 /*************************************************
452 * Find all the running network interfaces *
453 *************************************************/
455 /* Finding all the running interfaces is something that has os-dependent
456 tweaks, even in the IPv4 case, and it gets worse for IPv6, which is why this
457 code is now in the os-dependent source file. There is a common function which
458 works on most OS (except IRIX) for IPv4 interfaces, and, with some variations
459 controlled by macros, on at least one OS for IPv6 and IPv4 interfaces. On Linux
460 with IPv6, the common function is used for the IPv4 interfaces and additional
461 code used for IPv6. Consequently, the real function is called
462 os_common_find_running_interfaces() so that it can be called from the Linux
463 function. On non-Linux systems, the macro for os_find_running_interfaces just
464 calls the common function; on Linux it calls the Linux function.
466 This function finds the addresses of all the running interfaces on the machine.
467 A chain of blocks containing the textual form of the addresses is returned.
469 getifaddrs() provides a sane consistent way to query this on modern OSs,
470 otherwise fall back to a maze of twisty ioctl() calls
473 Returns: a chain of ip_address_items, each pointing to a textual
474 version of an IP address, with the port field set to zero
478 #ifndef NO_FIND_INTERFACES
480 #ifdef HAVE_GETIFADDRS
485 os_common_find_running_interfaces(void)
487 struct ifaddrs *ifalist = NULL;
488 ip_address_item *yield = NULL;
489 ip_address_item *last = NULL;
490 ip_address_item *next;
492 if (getifaddrs(&ifalist) != 0)
493 log_write(0, LOG_PANIC_DIE, "Unable to call getifaddrs: %d %s",
494 errno, strerror(errno));
497 for (ifa = ifalist; ifa != NULL; ifa = ifa->ifa_next)
499 if (ifa->ifa_addr->sa_family != AF_INET
501 && ifa->ifa_addr->sa_family != AF_INET6
502 #endif /* HAVE_IPV6 */
506 if ( !(ifa->ifa_flags & IFF_UP) ) /* Only want 'UP' interfaces */
509 /* Create a data block for the address, fill in the data, and put it on the
512 next = store_get(sizeof(ip_address_item));
515 (void)host_ntoa(-1, ifa->ifa_addr, next->address, NULL);
525 DEBUG(D_interface) debug_printf("Actual local interface address is %s (%s)\n",
526 last->address, ifa->ifa_name);
529 /* free the list of addresses, and return the chain of data blocks. */
531 freeifaddrs (ifalist);
535 #else /* HAVE_GETIFADDRS */
540 (1) Solaris 2 has the SIOGIFNUM call to get the number of interfaces, but
541 other OS (including Solaris 1) appear not to. So just screw in a largeish
542 fixed number, defined by MAX_INTERFACES. This is in the config.h file and
543 can be changed in Local/Makefile. Unfortunately, the www addressing scheme
544 means that some hosts have a very large number of virtual interfaces. Such
545 hosts are recommended to set local_interfaces to avoid problems with this.
547 (2) If the standard code is run on IRIX, it does not return any alias
548 interfaces. There is special purpose code for that operating system, which
549 uses the sysctl() function. The code is in OS/os.c-IRIX, and this code isn't
552 (3) Some experimental/developing OS (e.g. GNU/Hurd) do not have any means
553 of finding the interfaces. If NO_FIND_INTERFACES is set, a fudge-up is used
556 (4) Some operating systems set the IP address in what SIOCGIFCONF returns;
557 others do not, and require SIOCGIFADDR to be called to get it. For most of
558 the former, calling the latter does no harm, but it causes grief on Linux and
559 BSD systems in the case of IP aliasing, so a means of cutting it out is
563 /* If there is IPv6 support, and SIOCGLIFCONF is defined, define macros to
564 use these new, longer versions of the old IPv4 interfaces. Otherwise, define
565 the macros to use the historical versions. */
567 #if HAVE_IPV6 && defined SIOCGLIFCONF
568 #define V_ifconf lifconf
569 #define V_ifreq lifreq
570 #define V_GIFADDR SIOCGLIFADDR
571 #define V_GIFCONF SIOCGLIFCONF
572 #define V_GIFFLAGS SIOCGLIFFLAGS
573 #define V_ifc_buf lifc_buf
574 #define V_ifc_family lifc_family
575 #define V_ifc_flags lifc_flags
576 #define V_ifc_len lifc_len
577 #define V_ifr_addr lifr_addr
578 #define V_ifr_flags lifr_flags
579 #define V_ifr_name lifr_name
580 #define V_FAMILY_QUERY AF_UNSPEC
581 #define V_family ss_family
583 #define V_ifconf ifconf
584 #define V_ifreq ifreq
585 #define V_GIFADDR SIOCGIFADDR
586 #define V_GIFCONF SIOCGIFCONF
587 #define V_GIFFLAGS SIOCGIFFLAGS
588 #define V_ifc_buf ifc_buf
589 #define V_ifc_family ifc_family
590 #define V_ifc_flags ifc_flags
591 #define V_ifc_len ifc_len
592 #define V_ifr_addr ifr_addr
593 #define V_ifr_flags ifr_flags
594 #define V_ifr_name ifr_name
595 #define V_family sa_family
598 /* In all cases of IPv6 support, use an IPv6 socket. Otherwise (at least on
599 Solaris 8) the call to read the flags doesn't work for IPv6 interfaces. If
600 we find we can't actually make an IPv6 socket, the code will revert to trying
604 #define FAMILY AF_INET6
606 #define FAMILY AF_INET
609 /* OK, after all that preliminary stuff, here's the code. */
612 os_common_find_running_interfaces(void)
615 struct V_ifreq ifreq;
617 ip_address_item *yield = NULL;
618 ip_address_item *last = NULL;
619 ip_address_item *next;
621 char buf[MAX_INTERFACES*sizeof(struct V_ifreq)];
622 struct sockaddr *addrp;
626 /* We have to create a socket in order to do ioctls on it to find out
627 what we want to know. */
629 if ((vs = socket(FAMILY, SOCK_DGRAM, 0)) < 0)
633 debug_printf("Unable to create IPv6 socket to find interface addresses:\n "
634 "error %d %s\nTrying for an IPv4 socket\n", errno, strerror(errno));
635 vs = socket(AF_INET, SOCK_DGRAM, 0);
638 log_write(0, LOG_PANIC_DIE, "Unable to create IPv4 socket to find interface "
639 "addresses: %d %s", errno, strerror(errno));
642 /* Get the interface configuration. Some additional data is required when the
643 new structures are in use. */
645 ifc.V_ifc_len = sizeof(buf);
648 #ifdef V_FAMILY_QUERY
649 ifc.V_ifc_family = V_FAMILY_QUERY;
653 if (ioctl(vs, V_GIFCONF, CS &ifc) < 0)
654 log_write(0, LOG_PANIC_DIE, "Unable to get interface configuration: %d %s",
655 errno, strerror(errno));
657 /* If the buffer is big enough, the ioctl sets the value of ifc.V_ifc_len to
658 the amount actually used. If the buffer isn't big enough, at least on some
659 operating systems, ifc.V_ifc_len still gets set to correspond to the total
660 number of interfaces, even though they don't all fit in the buffer. */
662 if (ifc.V_ifc_len > sizeof(buf))
664 ifc.V_ifc_len = sizeof(buf);
666 debug_printf("more than %d interfaces found: remainder not used\n"
667 "(set MAX_INTERFACES in Local/Makefile and rebuild if you want more)\n",
671 /* For each interface, check it is an IP interface, get its flags, and see if
672 it is up; if not, skip.
674 BSD systems differ from others in what SIOCGIFCONF returns. Other systems
675 return a vector of ifreq structures whose size is as defined by the structure.
676 BSD systems allow sockaddrs to be longer than their sizeof, which in turn makes
677 the ifreq structures longer than their sizeof. The code below has its origins
678 in amd and ifconfig; it uses the sa_len field of each sockaddr to determine
681 This is complicated by the fact that, at least on BSD systems, the data in the
682 buffer is not guaranteed to be aligned. Thus, we must first copy the basic
683 struct to some aligned memory before looking at the field in the fixed part to
684 find its length, and then recopy the correct length. */
686 for (cp = buf; cp < buf + ifc.V_ifc_len; cp += len)
688 memcpy(CS &ifreq, cp, sizeof(ifreq));
691 len = sizeof(struct V_ifreq);
694 len = ((ifreq.ifr_addr.sa_len > sizeof(ifreq.ifr_addr))?
695 ifreq.ifr_addr.sa_len : sizeof(ifreq.ifr_addr)) +
696 sizeof(ifreq.V_ifr_name);
697 if (len > sizeof(addrbuf))
698 log_write(0, LOG_PANIC_DIE, "Address for %s interface is absurdly long",
703 /* If not an IP interface, skip */
705 if (ifreq.V_ifr_addr.V_family != AF_INET
707 && ifreq.V_ifr_addr.V_family != AF_INET6
711 /* Get the interface flags, and if the interface is down, continue. Formerly,
712 we treated the inability to get the flags as a panic-die error. However, it
713 seems that on some OS (Solaris 9 being the case noted), it is possible to
714 have an interface in this list for which this call fails because the
715 interface hasn't been "plumbed" to any protocol (IPv4 or IPv6). Therefore,
716 we now just treat this case as "down" as well. */
718 if (ioctl(vs, V_GIFFLAGS, CS &ifreq) < 0)
722 log_write(0, LOG_PANIC_DIE, "Unable to get flags for %s interface: %d %s",
723 ifreq.V_ifr_name, errno, strerror(errno));
726 if ((ifreq.V_ifr_flags & IFF_UP) == 0) continue;
728 /* On some operating systems we have to get the IP address of the interface
729 by another call. On others, it's already there, but we must copy the full
730 length because we only copied the basic length above, and anyway,
731 GIFFLAGS may have wrecked the data. */
733 #ifndef SIOCGIFCONF_GIVES_ADDR
734 if (ioctl(vs, V_GIFADDR, CS &ifreq) < 0)
735 log_write(0, LOG_PANIC_DIE, "Unable to get IP address for %s interface: "
736 "%d %s", ifreq.V_ifr_name, errno, strerror(errno));
737 addrp = &ifreq.V_ifr_addr;
740 memcpy(addrbuf, cp + offsetof(struct V_ifreq, V_ifr_addr),
741 len - sizeof(ifreq.V_ifr_name));
742 addrp = (struct sockaddr *)addrbuf;
745 /* Create a data block for the address, fill in the data, and put it on the
748 next = store_get(sizeof(ip_address_item));
751 (void)host_ntoa(-1, addrp, next->address, NULL);
753 if (yield == NULL) yield = last = next; else
759 DEBUG(D_interface) debug_printf("Actual local interface address is %s (%s)\n",
760 last->address, ifreq.V_ifr_name);
763 /* Close the socket, and return the chain of data blocks. */
769 #endif /* HAVE_GETIFADDRS */
771 #else /* NO_FIND_INTERFACES */
773 /* Some experimental or developing OS (e.g. GNU/Hurd) do not have the ioctls,
774 and there is no other way to get a list of the (IP addresses of) local
775 interfaces. We just return the loopback address(es). */
778 os_common_find_running_interfaces(void)
780 ip_address_item *yield = store_get(sizeof(address_item));
781 yield->address = US"127.0.0.1";
786 yield->next = store_get(sizeof(address_item));
787 yield->next->address = US"::1";
788 yield->next->port = 0;
789 yield->next->next = NULL;
792 DEBUG(D_interface) debug_printf("Unable to find local interface addresses "
793 "on this OS: returning loopback address(es)\n");
797 #endif /* NO_FIND_INTERFACES */
798 #endif /* FIND_RUNNING_INTERFACES */
803 /* ----------------------------------------------------------------------- */
805 /***********************************************************
806 * DNS Resolver Base Finder *
807 ***********************************************************/
809 /* We need to be able to set options for the system resolver(5), historically
810 made available as _res. At least one OS (NetBSD) now no longer provides this
811 directly, instead making you call a function per thread to get a handle.
812 Other OSs handle thread-safe resolver differently, in ways which fail if the
813 programmer creates their own structs. */
815 #if !defined(OS_GET_DNS_RESOLVER_RES) && !defined(COMPILE_UTILITY)
819 /* confirmed that res_state is typedef'd as a struct* on BSD and Linux, will
820 find out how unportable it is on other OSes, but most resolver implementations
821 should be descended from ISC's bind.
824 define _res (*__res_state())
825 identically. We just can't rely on __foo functions. It's surprising that use
826 of _res has been as portable as it has, for so long.
828 So, since _res works everywhere, and everything can decode the struct, I'm
829 going to gamble that res_state is a typedef everywhere and use that as the
834 os_get_dns_resolver_res(void)
839 #endif /* OS_GET_DNS_RESOLVER_RES */
841 /* ----------------------------------------------------------------------- */
843 /***********************************************************
845 ***********************************************************/
847 /* Most modern systems define int unsetenv(const char*),
850 #if !defined(OS_UNSETENV)
852 os_unsetenv(const unsigned char * name)
854 return unsetenv(CS name);
858 /* ----------------------------------------------------------------------- */
860 /***********************************************************
862 ***********************************************************/
864 /* Glibc allows getcwd(NULL, 0) to do auto-allocation. Some systems
865 do auto-allocation, but need the size of the buffer, and others
866 may not even do this. If the OS supports getcwd(NULL, 0) we'll use
867 this, for all other systems we provide our own getcwd() */
869 #if !defined(OS_GETCWD)
871 os_getcwd(unsigned char * buffer, size_t size)
873 return US getcwd(CS buffer, size);
877 # define PATH_MAX 4096
880 os_getcwd(unsigned char * buffer, size_t size)
882 char * b = CS buffer;
884 if (!size) size = PATH_MAX;
885 if (!b && !(b = malloc(size))) return NULL;
886 if (!(b = getcwd(b, size))) return NULL;
887 return buffer ? buffer : realloc(b, strlen(b) + 1);
891 /* ----------------------------------------------------------------------- */
896 /*************************************************
897 **************************************************
898 * Stand-alone test program *
899 **************************************************
900 *************************************************/
905 #ifdef CLOCKS_PER_SEC
906 #define REAL_CLOCK_TICK CLOCKS_PER_SEC
909 #define REAL_CLOCK_TICK CLK_TCK
911 #define REAL_CLOCK_TICK 1000000 /* SunOS4 */
916 int main(int argc, char **argv)
919 int fd = fileno(stdin);
922 printf("Testing restarting signal; wait for handler message, then type a line\n");
923 strcpy(buffer, "*** default ***\n");
924 os_restarting_signal(SIGALRM, sigalrm_handler);
926 if ((rc = read(fd, buffer, sizeof(buffer))) < 0)
927 printf("No data read\n");
931 printf("Read: %s", buffer);
935 printf("Testing non-restarting signal; should read no data after handler message\n");
936 strcpy(buffer, "*** default ***\n");
937 os_non_restarting_signal(SIGALRM, sigalrm_handler);
939 if ((rc = read(fd, buffer, sizeof(buffer))) < 0)
940 printf("No data read\n");
944 printf("Read: %s", buffer);
948 printf("Testing load averages (last test - ^C to kill)\n");
953 clock_t before = clock();
954 avg = os_getloadavg();
955 used = clock() - before;
956 printf("cpu time = %.2f ", (double)used/REAL_CLOCK_TICK);
959 printf("load average not available\n");
962 printf("load average = %.2f\n", (double)avg/1000.0);