Linux: Quickly create large files for testing
To create a 10 GB file:
fallocate -l 10G huge_file.dat
Related cards:
Remove resource fork files from a FAT volume on MacOS
Be careful!
The following solution will delete files on a volume. If you don't know exactly what you're doing, you can run into big trouble with your computer.
I play mp3 files on my car stereo that are stored on a SD-C...
How to create Excel sheets with spreadsheet gem and use number formats for cells like money or date
The following snippet demonstrates how you could create excel files (with spreadsheet gem) and format columns so that they follow a specific number format like currencies or dates do.
require 'rubygems...
How to rotate log files explicitly
Usually, the logrotate service takes care of renaming log files each night or so to avoid logs becoming huge. That will rename your.log to your.log.1, the next time to your.log.2.gz, etc. Here is how to make that happen out of band (you sh...
Rails: Assigning associations via HTML forms
Let's say we have posts with an attribute title that is mandatory.
Our example feature request is to tag these posts with a limited number of tags. The following chapters explain different approaches in Rails, how you can assign such a...
Unpoly: Loading large libraries on-demand
When your JavaScript bundle is so massive that you cannot load it all up front, I would recommend to load large libraries from the compilers that need it.
Compilers are also a good place to track whether the library has been loaded before. Note t...
Linux: How to print PDF files from the command line
Sometimes you may want to print files from the command line, especially when you have lots of them.
You can use lp for that.
To print a single example.pdf file on your default printer, simply say:
lp example.pdf
lp accepts multipl...
How to use Ubuntu in English, but still show German formats
If you want to have an English Ubuntu UI, but still see dates, money amounts, paper formats, etc. in German formats, you can fine-tune your /etc/default/locale like this:
LANG="en_US.UTF-8"
LC_CTYPE="de_DE.UTF-8"
LC_NUMERIC="de_DE.U...
New Firefox and gem versions for our Selenium testing environment (Ubuntu 14.04+)
Firefox 5.0.1, which we were using for most Rails 2.3 projects, does not run on Ubuntu 14.04 any more. Here is how to update affected projects.
- Update (or create)
.firefox-versionwith the content:24.0
If you haven't installed Firefo...
Ubuntu MATE: Custom time format for clock panel widget
- Run
dconf-editor(as your user) - Go to
org / mate / panel / objects / clock / prefs - Change the key
formattocustom - Change the key
custom-formatto astrftimeformat string
A good, s...
Consul 0.3.0 has a shortcut to quickly create an action map for CRUD controllers
In moderately complex authorization scenarios you will often find yourself writing a map like this:
class NotesController < ApplicationController
power :notes, :map => {
[:edit, :update] => :updatable_notes
[:new, :creat...