Revert to Fedora kernel-2.6.17-1.2187_FC5 patched with vs2.0.2.1; there are too many...

[linux-2.6.git] / Documentation / watchdog / watchdog-api.txt

diff --git a/Documentation/watchdog/watchdog-api.txt b/Documentation/watchdog/watchdog-api.txt
index 958ff3d..21ed511 100644 (file)
--- a/Documentation/watchdog/watchdog-api.txt
+++ b/Documentation/watchdog/watchdog-api.txt
@@ -34,7 +34,22 @@ activates as soon as /dev/watchdog is opened and will reboot unless
 the watchdog is pinged within a certain time, this time is called the
 timeout or margin.  The simplest way to ping the watchdog is to write
 some data to the device.  So a very simple watchdog daemon would look
 the watchdog is pinged within a certain time, this time is called the
 timeout or margin.  The simplest way to ping the watchdog is to write
 some data to the device.  So a very simple watchdog daemon would look

-like this source file:  see Documentation/watchdog/src/watchdog-simple.c
+like this:
+
+#include <stdlib.h>
+#include <fcntl.h>
+
+int main(int argc, const char *argv[]) {
+       int fd=open("/dev/watchdog",O_WRONLY);
+       if (fd==-1) {
+               perror("watchdog");
+               exit(1);
+       }
+       while(1) {
+               write(fd, "\0", 1);
+               sleep(10);
+       }
+}

 
 A more advanced driver could for example check that a HTTP server is
 still responding before doing the write call to ping the watchdog.
 
 A more advanced driver could for example check that a HTTP server is
 still responding before doing the write call to ping the watchdog.


@@ -95,40 +110,7 @@ current timeout using the GETTIMEOUT ioctl.
     ioctl(fd, WDIOC_GETTIMEOUT, &timeout);
     printf("The timeout was is %d seconds\n", timeout);
 
     ioctl(fd, WDIOC_GETTIMEOUT, &timeout);
     printf("The timeout was is %d seconds\n", timeout);
 

-Pretimeouts:
-
-Some watchdog timers can be set to have a trigger go off before the
-actual time they will reset the system.  This can be done with an NMI,
-interrupt, or other mechanism.  This allows Linux to record useful
-information (like panic information and kernel coredumps) before it
-resets.
-
-    pretimeout = 10;
-    ioctl(fd, WDIOC_SETPRETIMEOUT, &pretimeout);
-
-Note that the pretimeout is the number of seconds before the time
-when the timeout will go off.  It is not the number of seconds until
-the pretimeout.  So, for instance, if you set the timeout to 60 seconds
-and the pretimeout to 10 seconds, the pretimout will go of in 50
-seconds.  Setting a pretimeout to zero disables it.
-
-There is also a get function for getting the pretimeout:
-
-    ioctl(fd, WDIOC_GETPRETIMEOUT, &timeout);
-    printf("The pretimeout was is %d seconds\n", timeout);
-
-Not all watchdog drivers will support a pretimeout.
-
-Get the number of seconds before reboot:
-
-Some watchdog drivers have the ability to report the remaining time
-before the system will reboot. The WDIOC_GETTIMELEFT is the ioctl
-that returns the number of seconds before reboot.
-
-    ioctl(fd, WDIOC_GETTIMELEFT, &timeleft);
-    printf("The timeout was is %d seconds\n", timeleft);
-
-Environmental monitoring:
+Envinronmental monitoring:

 
 All watchdog drivers are required return more information about the system,
 some do temperature, fan and power level monitoring, some can tell you
 
 All watchdog drivers are required return more information about the system,
 some do temperature, fan and power level monitoring, some can tell you


@@ -187,10 +169,6 @@ The watchdog saw a keepalive ping since it was last queried.
 
        WDIOF_SETTIMEOUT        Can set/get the timeout
 
 
        WDIOF_SETTIMEOUT        Can set/get the timeout
 

-The watchdog can do pretimeouts.
-
-       WDIOF_PRETIMEOUT        Pretimeout (in seconds), get/set
-

 
 For those drivers that return any bits set in the option field, the
 GETSTATUS and GETBOOTSTATUS ioctls can be used to ask for the current
 
 For those drivers that return any bits set in the option field, the
 GETSTATUS and GETBOOTSTATUS ioctls can be used to ask for the current