Pacnew_scripts: scripts to merge some .pacnew files after an upgrade

Question

info page: http://xyne.archlinux.ca/info/pacnew_scripts
I was updating my old system which doesn't get turned on that often and had to deal with about 15 pacnew files. Most only required a simple "mv /path/to/file{.pacnew,}" but some required merging. I found a script that I had written a while ago to merge /etc/group.pacnew, made some changes, made a copy which can handle gshadow, then wrote scripts to handle the pacman mirrorlist and locale.gen.
Thus the pacnew_scripts package was born.
infopage wrote:
This package contains scripts which can help merge .pacnew files after a pacman upgrade. These scripts print their results to STDOUT and thus do NOT make any changes to the files. It is up to the user to inspect the output and, if satisfied, redirect it to the original file and then delete the .pacnew file.
The scripts accept "-c" and "--compare" as options and will display relevant information about differences between the files. For group and gshadow, this will display 3 columns to compare the original, .pacnew and merged files and will use colors to highlight changes. For the mirrorlist and locale.gen, it will check that all settings in the original file are available in the new file and print out a list of any that aren't (e.g. if one of your current mirrors has been dropped from the mirrorlist, it will be listed in the output).
I'll probably add scripts as I go. I might also merge the scripts to avoid some redundancy but I decided to keep them simple for now. merge_pacnew_locale_gen is actually very generic and works on the mirrorlist and probably other files as well. If you find any, let me know.
Last edited by Xyne (2010-03-21 13:03:34)

Answer 1

beroal wrote:
I'm really astonished that you interpreted my post as an advertisement of "diffpac".
Xyne wrote:Have you even tried these scripts and compared them to the alternatives that you've proposed? … you can at least post comments based on an informed comparison.
I expected such a comparison from you. If "pacnew_scripts" merges files automatically, what algorithm does it use?
I didn't interpret it as advertisement. It seemed that you read the basic description of what this does and concluded that something else already does the same thing. Following on the tail of the previous posts I felt that your post was somewhat rude because it implies that this is useless. Obviously that is relative, but even so I see no point of posting in this thread to express it, even indirectly.
I admit that I may have interpreted your post the wrong way and if I did then I apologize, but even then I don't understand why you felt the need to post what you did in a contribution thread.
As for algorithms, there are different scripts and they use different algorithms. The group and gshadow scripts create hash representations of the groups in the original and .pacnew files. Groups which only exist in one of the files pass through untouched. Groups which exist in both have their members combined, which usually means that the original simply passes through. Using the "--compare" option, three aligned columns are displayed which clearly shows existing groups, new groups and the results of merging, with colors used to highlight all changes.
The mirrorlist script creates a list of selected servers in the current mirrorlist and generates a new mirrorlist from the .pacnew mirrorlist with all servers in the generated list uncommented, if they exist. Passing the "--compare" option will simply check if all the currently selected mirrors still exist in the new mirrorlist (they might not if they're dropped) and prints out a list of any that aren't.
The locale_gen script does the same thing for currently enabled locales.
Also note that all of the results are printed to STDOUT so no files are actually changes. It isn't fully "automatic" and the user is expected to sanity-check the results before overwriting the target files.