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diff --git a/static/freebsd/man4/watchdog.4 3.html b/static/freebsd/man4/watchdog.4 3.html new file mode 100644 index 00000000..4449d3c3 --- /dev/null +++ b/static/freebsd/man4/watchdog.4 3.html @@ -0,0 +1,186 @@ +<table class="head"> + <tr> + <td class="head-ltitle">WATCHDOG(4)</td> + <td class="head-vol">Device Drivers Manual</td> + <td class="head-rtitle">WATCHDOG(4)</td> + </tr> +</table> +<div class="manual-text"> +<section class="Sh"> +<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> +<p class="Pp"><code class="Nm">watchdog</code> — + <span class="Nd">hardware and software watchdog</span></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> +<p class="Pp"><code class="In">#include + <<a class="In">sys/watchdog.h</a>></code></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> +<p class="Pp">The <code class="Nm">watchdog</code> facility is used for + controlling hardware and software watchdogs.</p> +<p class="Pp">The device <span class="Pa">/dev/fido</span> supports several + optional <a class="Xr">ioctl(2)</a> calls for configuration, and responds to + a set of operational <a class="Xr">ioctl(2)</a> calls:</p> +<dl class="Bl-tag"> + <dt id="WDIOCPATPAT"><a class="permalink" href="#WDIOCPATPAT"><code class="Dv">WDIOCPATPAT</code></a></dt> + <dd>Pat the watchdog.</dd> + <dt id="WDIOC_CONTROL"><a class="permalink" href="#WDIOC_CONTROL"><code class="Dv">WDIOC_CONTROL</code></a></dt> + <dd>Enable, disable, or reset the watchdog.</dd> +</dl> +<p class="Pp">The <code class="Dv">WDIOCPATPAT</code> <a class="Xr">ioctl(2)</a> + call takes a single argument which represents a timeout value specified as a + <var class="Vt">sbintime_t</var> of the timeout period for the watchdog.</p> +<p class="Pp">The <code class="Dv">WDIOCPATPAT</code> <a class="Xr">ioctl(2)</a> + call will return success if just one of the available + <a class="Xr">watchdog(9)</a> implementations supports setting the timeout + to the specified timeout. This means that at least one watchdog is armed. By + default, this will be a hardware watchdog if one is present, but if no + hardware watchdog is able to process the request, a default software + watchdog is enabled. If the call fails, for instance if none of + <a class="Xr">watchdog(9)</a> implementations support the timeout length, + all watchdogs are disabled and must be explicitly re-enabled.</p> +<p class="Pp">To disable the watchdogs use the + <code class="Dv">WDIOC_CONTROL</code> <a class="Xr">ioctl(2)</a> call with + the <code class="Dv">WD_CTRL_DISABLE</code> flag. If disarming the + watchdog(s) failed an error is returned. The watchdog might still be armed! + To reenable the watchdogs use the <code class="Dv">WDIOC_CONTROL</code> + <a class="Xr">ioctl(2)</a> call with the + <code class="Dv">WD_CTRL_ENABLE</code> flag. Another way to pat the watchdog + is with the <code class="Dv">WDIOC_CONTROL</code> <a class="Xr">ioctl(2)</a> + call passing the <code class="Dv">WDIOC_CTRL_RESET</code> flag.</p> +<p class="Pp">The optional configuration <a class="Xr">ioctl(2)</a> commands are + listed here, along with the type of the parameter used. Examples of their + use can be found in <a class="Xr">watchdogd(8)</a>.</p> +<dl class="Bl-tag"> + <dt id="WDIOC_SETTIMEOUT"><a class="permalink" href="#WDIOC_SETTIMEOUT"><code class="Dv">WDIOC_SETTIMEOUT</code></a> + <var class="Fa">sbintime_t</var></dt> + <dd>set/reset the timer</dd> + <dt id="WDIOC_GETTIMEOUT"><a class="permalink" href="#WDIOC_GETTIMEOUT"><code class="Dv">WDIOC_GETTIMEOUT</code></a> + <var class="Fa">sbintime_t</var></dt> + <dd>get total timeout</dd> + <dt id="WDIOC_GETTIMELEFT"><a class="permalink" href="#WDIOC_GETTIMELEFT"><code class="Dv">WDIOC_GETTIMELEFT</code></a> + <var class="Fa">sbintime_t</var></dt> + <dd>get time left</dd> + <dt id="WDIOC_GETPRETIMEOUT"><a class="permalink" href="#WDIOC_GETPRETIMEOUT"><code class="Dv">WDIOC_GETPRETIMEOUT</code></a> + <var class="Fa">sbintime_t</var></dt> + <dd>get the pre-timeout</dd> + <dt id="WDIOC_SETPRETIMEOUT"><a class="permalink" href="#WDIOC_SETPRETIMEOUT"><code class="Dv">WDIOC_SETPRETIMEOUT</code></a> + <var class="Fa">sbintime_t</var></dt> + <dd>set the pre-timeout</dd> + <dt id="WDIOC_SETPRETIMEOUTACT"><a class="permalink" href="#WDIOC_SETPRETIMEOUTACT"><code class="Dv">WDIOC_SETPRETIMEOUTACT</code></a> + <var class="Fa">int</var></dt> + <dd>Set the action when a pre-timeout occurs (see + <code class="Li">WD_SOFT_*</code> below).</dd> + <dt id="WDIOC_SETSOFT"><a class="permalink" href="#WDIOC_SETSOFT"><code class="Dv">WDIOC_SETSOFT</code></a> + <var class="Fa">int</var></dt> + <dd>Use an internal software watchdog instead of hardware. There is also an + external software watchdog, which is used by default if no hardware + watchdog was attached.</dd> + <dt id="WDIOC_SETSOFTTIMEOUTACT"><a class="permalink" href="#WDIOC_SETSOFTTIMEOUTACT"><code class="Dv">WDIOC_SETSOFTTIMEOUTACT</code></a> + <var class="Fa">int</var></dt> + <dd>Set the action when a soft timeout occurs.</dd> +</dl> +<p class="Pp">The actions that may be specified for the pre-timeout or the + internal software watchdog are listed here. Multiple actions can be + specified by ORing values together.</p> +<dl class="Bl-tag"> + <dt id="WD_SOFT_PANIC"><a class="permalink" href="#WD_SOFT_PANIC"><code class="Dv">WD_SOFT_PANIC</code></a></dt> + <dd>panic</dd> + <dt id="WD_SOFT_DDB"><a class="permalink" href="#WD_SOFT_DDB"><code class="Dv">WD_SOFT_DDB</code></a></dt> + <dd>enter debugger</dd> + <dt id="WD_SOFT_LOG"><a class="permalink" href="#WD_SOFT_LOG"><code class="Dv">WD_SOFT_LOG</code></a></dt> + <dd>log(9)</dd> + <dt id="WD_SOFT_PRINT"><a class="permalink" href="#WD_SOFT_PRINT"><code class="Dv">WD_SOFT_PRINT</code></a></dt> + <dd>printf(9)</dd> +</dl> +</section> +<section class="Sh"> +<h1 class="Sh" id="RETURN_VALUES"><a class="permalink" href="#RETURN_VALUES">RETURN + VALUES</a></h1> +<p class="Pp">The <code class="Dv">WDIOCPATPAT</code> <a class="Xr">ioctl(2)</a> + returns zero on success and non-zero on failure.</p> +<dl class="Bl-tag"> + <dt>[<code class="Er">EOPNOTSUPP</code>]</dt> + <dd>No watchdog present in the kernel or none of the watchdogs supports the + requested timeout value (timeout value other than 0).</dd> + <dt>[<code class="Er">EOPNOTSUPP</code>]</dt> + <dd>Watchdog could not be disabled (timeout value of 0).</dd> + <dt>[<code class="Er">EINVAL</code>]</dt> + <dd>Invalid flag combination passed.</dd> +</dl> +<p class="Pp">The configuration <a class="Xr">ioctl(2)</a> operations return + zero on success and non-zero on failure.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="EXAMPLES"><a class="permalink" href="#EXAMPLES">EXAMPLES</a></h1> +<div class="Bd Bd-indent Li"> +<pre>#include <paths.h> +#include <sys/watchdog.h> + +#define WDPATH "/dev/" _PATH_WATCHDOG +int wdfd = -1; + +static void +wd_init(void) +{ + wdfd = open(WDPATH, O_RDWR); + if (wdfd == -1) + err(1, WDPATH); +} +static void +wd_reset(u_int timeout) +{ + if (ioctl(wdfd, WDIOCPATPAT, &timeout) == -1) + err(1, "WDIOCPATPAT"); +} + +/* in main() */ +wd_init(); +wd_reset(WD_ACTIVE|WD_TO_8SEC); +/* potential freeze point */ +wd_reset(WD_TO_NEVER);</pre> +</div> +<p class="Pp">Enables a watchdog to recover from a potentially freezing piece of + code.</p> +<p class="Pp"></p> +<div class="Bd Bd-indent"><code class="Li">options SW_WATCHDOG</code></div> +<p class="Pp">in your kernel config forces a software watchdog in the kernel to + be configured even if a hardware watchdog is configured, dropping to KDB or + panicking when firing, depending on the KDB and KDB_UNATTENDED kernel + configuration options.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE + ALSO</a></h1> +<p class="Pp"><a class="Xr">watchdogd(8)</a>, <a class="Xr">watchdog(9)</a></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> +<p class="Pp">The <code class="Nm">watchdog</code> code first appeared in + <span class="Ux">FreeBSD 5.1</span>.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="AUTHORS"><a class="permalink" href="#AUTHORS">AUTHORS</a></h1> +<p class="Pp">The <code class="Nm">watchdog</code> facility was written by + <span class="An">Poul-Henning Kamp</span> + <<a class="Mt" href="mailto:phk@FreeBSD.org">phk@FreeBSD.org</a>>. The + software watchdog code and this manual page were written by + <span class="An">Sean Kelly</span> + <<a class="Mt" href="mailto:smkelly@FreeBSD.org">smkelly@FreeBSD.org</a>>. + Some contributions were made by <span class="An">Jeff Roberson</span> + <<a class="Mt" href="mailto:jeff@FreeBSD.org">jeff@FreeBSD.org</a>>.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="BUGS"><a class="permalink" href="#BUGS">BUGS</a></h1> +<p class="Pp">The <code class="Dv">WD_PASSIVE</code> option has not yet been + implemented.</p> +</section> +</div> +<table class="foot"> + <tr> + <td class="foot-date">January 2, 2018</td> + <td class="foot-os">FreeBSD 15.0</td> + </tr> +</table> |