Inappropriate use of time rules

It is important to know the correct use of time rules.

Your view interprets time rules with respect to the create version event record written by the checkin command. The checkin is read from the system clock on the VOB server host. If that clock is out of sync with the clock on the view server host, your attempt to roll back the clock might fail. Thus, do not strive for extreme precision with time rules: select a time that is well before the actual cutoff time (for example, a full hour before, or in the middle of the night).

Do not use time rules to freeze a view to the current time immediately before you start a build. Allow the reference time facility of clearmake to perform this service. Here is an inappropriate use scenario:

1. You check in version 12 of util.c at 7:05 P.M. on your host. You do not know that clock skew on the VOB host causes the time 7:23 P.M. to be entered in the create version event record.
2. To freeze your view, you change your config spec to include this rule:

   element * /main/LATEST -time 19:05

3. You issue a clearmake command immediately (at 7:06 P.M.) to build a program that uses util.c. When selecting a version of this element to use in the build, your view consults the event history of util.c and rejects version 12, because the 7:23 P.M. time stamp is too late for the -time configuration rule.