ctime is a safe include for time.h so that is really why you are getting this.
So the documentation you should look at is the time functions in the runtime routines. (
http://msdn.microsoft.com/en-us/library/w4ddyt9h.aspx for time)
The two functions you want in particular are gmtime and mktime. gmtime reads a time_t and converts it to a tm structure, mktime takes a tm structure and outputs a time_t.
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