The CLOCK field on the history tables... what does it mean?

[r-br]

The history_xxx tables have three fields: itemid, clock and value.
The clock field has type INT... what is it, exactly? Timestamp?

I'm doing some experiments in C, and I'd like to get the actual date and time from that clock value.
How could I do it?

[nelsonab]

It is the Unix time stamp of that data point. Unix time stamps are seconds since the Epoch (Jan 1, 1970 00:00 GMT).

[r-br]

Thank you.