Continuing to work during a build
As your build progresses, other developers continue to work on their files and might check in new versions of elements that your build uses.
If your build takes an hour to complete, you do not want build scripts executed early in the build to use version 6 of a header file and scripts executed later to use version 7 or 8.
To prevent such inconsistencies, any version whose selection is based on a LATEST config spec rule is locked out if it is checked-in after the instant that clearmake was invoked. The moment that the clearmake build session begins is the build reference time.
The same reference time is reported in each configuration record produced during the build session, even if the session lasts hours (or days):
% cleartool catcr hello.o
Target hello.o built by drp.dvt
Host "fermi" running OSF1 V1.3 (alpha)
Reference Time 26-Feb-03.16:53:58, this audit started
26-Feb-03.16:54:10 ...
When determining whether an object was created before or after the build reference time, clearmake adjusts for clock skew, the inevitable small differences among the system clocks on different hosts. For more information about build sessions, see Build sessions, subsessions, and hierarchical builds.