Depends on what you mean by "exactly". If it's ok to be a second or so off, it may be enough to just keep sleeping for 1 second and then checking the time to see if it's "exactly" when you need to do the next step. Just keep synchronized on system time. Beyond that, you'll have to get into milliseconds, which I'm sure someone else can supply code for (it's been too long and I don't remember the commands).

In reply to Re: RRD-Ping getting values on right interval by TJPride
in thread RRD-Ping getting values on right interval by hello_world

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