There are various ways to run external commands from within Ruby, but the most powerful ones are Open3.capture3 and Open3.popen3. Since those can do almost everything you would possibly need in a clean way, I prefer to simply...

This can be helpful when you need the latest file inside a directory for processing in a shell script:

ls -1tr * | tail -1

Used switches

The -1 switch makes ls return 1 file per line, -t orders by modification time and...

In order to open a MySQL shell without the need to enter user and password, you can say the following in any Rails 2 project:

script/dbconsole -p

In Rails 3 you can say:

rails dbconsole -p

If you'd like to enter a database for an envir...

If you want to manually check if e-mail delivery works on a machine by sending an e-mail you can run the following:
mail -s Test someone@example.com < /dev/null

This will send an empty e-mail with "Test" as its subject to `someone@example.com...

When you print something from within your .bashrc file you will run into trouble when copying something onto your machine using scp for example.

This is because the output from your .bashrc interferes with scp. The solution is to decide w...

We regularly need to connect to the server in order to e.g. access the production console. Guessing the Capistrano deploy user and then again guessing the right directory on the server is awkward, so we wrote a script that parses config/deploy and...

I recently noticed that better_errors allows you to to open files from within your favorite editor. However it was not so easy to get rubymine:// links to work ...