command line

If you are working on the Linux command line then sometimes you'll do a search to find out how to run a command that performs a task. I don't usually copy and paste commands in unless I can see what is going on, which used to mean spending time going through man pages and documentation trying to find out what this or that flag does.

That all changed when I found explainshell.com, which will extract the parameters of a command and tell you all about what the different flags will do.

Grep is a really powerful tool for finding things in files. I often use it to scan for plugins in the Drupal codebase or to scan through a CSV or log file for data.

For example, to scan for user centric ViewsFilter plugins in the Drupal core directory use this command (assuming you are relative to the core directory).

grep "@ViewsFilter(\"user" -r core

The -r flag here recursively scans the 'core' directory. This command returns the following output.

The other day I was trying to print some output to the command line and then overwrite the output afterwards. It turns out that there are a couple of ways to do this so I thought I would detail a few of them here.

By far the simplest way of doing this is to run the "clear" command, which we can run via the system() function in PHP. This will clear the output of the command line ready for you to print out whatever you need. The downside to this is that the entire terminal window is cleared. Another downside is that once the output is complete scrolling up will reveal the output that was cleared out.

Whilst it is possible to view the contents of an SSL cert from within most modern browsers I occasionally find the need to use the command line to find out the same information. I find this useful when renewing certificates as browsers can occasionally cache certificates for longer than expected, causing false results.