MacOS – Unpacking a installer is failing with pkgutil tool

Yes, you can. plug in the disk, boot up in it by holding down option, select the disk, and and then run disk utility from the main window.

Why do this however, when you have the Restore partition available to do this without a disk?

When I first commented on your question, I was hindered by not having discovered httpd.conf on my own system. Now I have found it, however, and I can find out what packages owns it as follows:

; pkgutil --file-info /private/etc/apache2/httpd.conf
volume: /
path: /private/etc/apache2/httpd.conf

pkgid: com.apple.pkg.BSD
pkg-version: 10.8.0.1.1.1306847324
install-time: 1352382423
uid: 0
gid: 0
mode: 644

Note: com.apple.pkg.BSD is a package name, not a filename. You can find a list of all packages that pkgutil knows about by running

pkgutil --packages

Also note that running the above command on /etc/apache2/httpd.conf does not yield a useful result, because /etc is a symbolic link to /private/etc.