Category Archives: Mac

Remove duplicate of files

I had a number of folders on my MacBook. Each of them a full backup from a mobil phone, from different dates. To clean it up, I decided to only keep the elements in each folder, not present in the next folder.

To do this, I started by creating a diff output

diff -q -s folder1/ folder2 > ~/Desktop/diffOutput.txt

This output contained both the uniq files, but also list the identical files.

So to get a list of the identical file names, I used grep and cut, like the following.

grep identical diffoutput.txt | grep -e "folder1/.* and" -o | cut -f2 -d'/' | cut -f1 -d' ' > ~/Desktop/diffParsed.txt

The last thing is to remove the identical files.

cat ~/Desktop/diffParsed.txt | xargs rm

Doing presentations on my Mac

I am in the middle of creating some presentations about Git. A version control system, I have successfully integrated into my department at Phase One. So I could of cause use Microsoft PowerPoint, or Apple Keynote.
Though is there a tool, which I am more used to, and even though it is harder to learn, superior in many ways. The tool is LaTeX, Beamer, Emacs and AuxTex.

So why do I consider this a superior solution.

  • The files are text files, and easy to version control, including being able to merge changes.
  • Depending on target, It will guide the presentation design against a PDF output, meaning you will not create distracting animations etc.
  • Being designed to PDF output also means it easy to prints handout etc.
  • The tools is true cross platform, working on Windows, Mac OS X, Linux and *BSD. So you data are not locked to a vendor.

The bad thing is the learning curve and knowhow needed for using the tool. PowerPoint and Keynote are much easier to get started with.

So knowing the tool from my many years working with Linux, the new part was to install the tools on my Mac. It was though pretty easy to install, as I am already using MacPorts.

  • LaTeX. The easiest way to install LaTeX using MacPorts, is the texlive package. This can be installed in a basis, medium or full variants. I just select the medium variants, as it contains the package I need.
sudo port install texlive +medium
  • Beamer is a tetex package, containing what is needed for creating presentation in LaTeX. Again installed by a MacPort command.
sudo port install tex-beamerposter
  • Emacs is an old family of editors, started in 1975 by Richard Stallman. The version I choose to use on my Mac is called emacs-app in Macport, and contains a Cocoa edition of GNU emacs. Cocoa means the editor uses the Macs native graphical toolkit.
sudo port install emacs-app
  • AucTex is a package originally from Aalborg University, which is a major emacs mode for editing TeX files. It is installed by the following command.
sudo port install auctex +emacs_app

When everything is installed you will need to bind it together in the .emacs file. This is the configuration file for emacs, and there are many examples for how to create one around on the internet. Personally I see it as a continued work in progress; there never can be finished. Later I will maybe give some tips as comments to this post.