[uClibc] clock() for long-running process
Manuel Novoa III
mjn3 at codepoet.org
Tue May 11 13:18:28 UTC 2004
On Tue, May 11, 2004 at 03:04:38PM +0200, Joakim Tjernlund wrote:
> > If you're trying to measure elapsed wall clock time on linux and you need
> > only second accuracy, you can use the difference in system uptime.
> >
> > #include <sys/sysinfo.h>
> >
> > /* Return system uptime in seconds. */
> >
> > long uptime(void)
> > {
> > struct sysinfo info;
> >
> > sysinfo(&info);
> >
> > return info.uptime;
> > }
>
> OK, thanks. Hmm, why is info.uptime a long instead of an unsigned long? What happens when
> info.uptime reaches negative values? I would guess that uptime just keeps counting until
> it wraps to 0?
No idea. But even the minimum allowed value for LONG_MAX is a bit over
68 years of seconds. So I really doubt you need to worry about wrapping
here. :-)
Manuel
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