To batch deinstall packages that were installed by mistake via pkgsrc

[Isaac Isao Saito <130s%lateeye.net@localhost>]

Hi pkgsrc-users,

I'm new to pkgsrc. By accident, I triggered building all the packages
under %PKGSRC_HOME%/devel, which didn't finish after 7+ hours when I
noticed I should halt and see why and noticed that I was in that
folder (I was supposed to be in a subfolder there). More specifically,
the commands were:

    $ cd %PKGSRC_HOME%/devel
    $ bmake     (this lasted forever until I C-c)

I assume this built so many stuff already and added unnecessary
several giga-byte on the file system.

Is there a way to clearly differentiate the packages that were
installed by the command above, and de-install them?

I though if `pkg_info` returns the date installed that could be
useful, but it actually doesn't.

Thank you!

--
Isaac