I have not identified a specific cause of my problem yet and would ask anyone more qualified to have a look. Here is what happened:
On a Slackware 12.1 system I decided to try an application evolus-pencil using the current SW 14 SBo script to build the package.
The script repackages the binary from a noarch.rpm. The MD5 was good, no errors making the package.
I then used
sudo installpkg evolus-pencil-1.3-noarch-1_SBo.tgz |tee ~/install_notes/evolus-pencil_install
...to install it and... and immediately could do nothing else!
Using basic things like
resulted in a bash error message.
I found that the /usr directory permissions had changed to 744, as well as /usr/lib, /usr/bin and /usr/share!
Fearing a corrupted hard drive I first backed up anything of value then probed around my other partitions. Eventually I rebooted into a Slackware 14 installation on another partition of the same drive - all OK.
It turned out that the directory permissions listed above seemed to have been the only notable changes (fortunately it was not a recursive change!).
Nothing in the logs that caught my attention... I cannot see anything in the Slackbuild or doinst.sh that would cause this. The /usr paths from the noarch.rpm are in fact 744, but I would not expect that to result in such a critical change on my system!
Anyway, I reset the /usr, /usr/lib and /usr/bin directories to 755 and booted back into my slackware 12.1 partition... and uninstalled evolus-pencil! All seems OK but I am still looking into what might have happened and am fearful of other changes.
If anyone with a little time on their hands and a good eye for build scripts would take a look at the SBo script and resulting package, it might save someone else some heartache!
EDIT - I have xulrunner-126.96.36.199 installed - a dependency of evolus-pencil
EDIT #2 - I will write the maintainer, but would like to know there is actually a problem with the script and be able to describe it before shouting "Your script is broken"! It might just be the phase of the moon...
EDIT #3 - I rebuilt and reinstalled and it is definitely the installation that canges those permissions
EDIT #4 - OK, modifying the Slackbuild to set permissions on the extracted rpm tree before building the package makes it install correctly (wrt permissions). I did not think that installpkg changed parent directory permissions - but obviously not correct.
So, the SBo script will corrupt the system as it exists - I'll write the maintainer...
(After all of that it did not work due to too old xulrunner, and I am not up to rebuilding that tonight...)