per-file-timestamps

[Michael Talbot-Wilson]

I'm a new Bazaar user.

I took an existing source tree and put it under Bazaar with bzr init
and cp -aR, then committed with bzr commit.  After the commit there
were files with mtimes prior to the evolution of modern man:

drwxr-xr-x 2    4096 1998-02-25 07:01 Gui/
-rw-r--r-- 1   28598 1998-02-24 18:04 Installation
-rw-r--r-- 1   33417 1998-02-24 18:04 Installation.html
-rw-r--r-- 1    4355 1995-12-02 06:02 License

Then I exported with bzr export --per-file-timestamps filename.tar.gz
and unpacked the resulting file.  The files had not been modified but
they had changed mtimes:

drwxr-xr-x 2    4096 2012-10-08 13:04 Gui/
-rw-r--r-- 1   28598 2012-10-08 11:26 Installation
-rw-r--r-- 1   33417 2012-10-08 11:26 Installation.html
-rw-r--r-- 1    4355 2012-10-08 11:26 License

I thought --per-file-timestamps would export with the existing
mtimes.  I thought and think that if a file has not been m'ed its mtime
should not change.

What am I doing wrong?  How is bazaar made to preserve mtimes when
there is no modification?

Incidentally I waited till about 13:04 before unpacking with tar xzf
but still don't underst... never mind.  What about the file mtimes?

On Linux version 2.6.29.6, ext4.