Re: function for clockticks since 1980?

Peter J. Holzer wrote:

Linux and other POSIX-compatible systems have the gettimeofday function,
which returns the time in seconds and microseconds since the epoch. Be
warned that the actual resolution of the clock can be much coarser:
Linux/x86 actually uses a microsecond clock, but some other Unixes have
resolutions of something between 1/60 to 1/1024 of a second.

Linux/x86 (and possibly other platforms as well) are able to offer
sub-jiffie resolution by interpolating cycle counter values.

On Linux/x86 the /resolution/ is less than 1 ns when using the TSC
on a CPU faster than 1 GHz.

(Contrast resolution with precision and accuracy.)
.

Relevant Pages

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