If I register an atexit handler, and then call os.execv, the handler is not invoked before my process changes over to the new program.  Shouldn't it be?  My program is ending, so my atexit handlers should be invoked.

This is based on this coverage.py bug:  https://bitbucket.org/ned/coveragepy/issue/43/coverage-measurement-fails-on-code  If the atexit handlers were invoked as part of os.execv, it would work properly.