[p4] interchanges

[John Hopkins]

We are also finding the interchanges command very useful.  We insert
the command's output to list the changes that have been submitted
since the last successful build.

I have found based on observations that the performance of the
interchanges command is noticeably faster now that we've upgraded from
2005.1 to 2006.1 (the upgrade went smoothly, btw).

Not specific to interchanges, we are however finding that some files
fail to be picked up by 'p4 integrate -Idt' and have resorted to
following up the -Idt integrate with the undocumented -1 (that's "dash
one") option to integrate (then backing out unchanged files with the
help of p4 diff -sr | p4 -x- revert).  It is difficult to say why
Perforce missed certain changes - we are not yet sure if it is a bug
or perhaps a deep integration history that is causing the issue.  This
problem still exists with 2006.1.  It would be nice if integrate had
an option to 'show its integrate plan' similar to a SQL database's
'show query plan' functionality so one could easily see why a change
being missed.

Back to the p4 interchanges topic, I would like to know what
Perforce's plans are to make interchanges a 'documented' command since
it is written about everywhere (including their new book) and probably
used by many people.

John