Run PJL Commands From A Shell Script

I love learning obscure and under-utilized things in the tech world; PJL commands fit that bill.  You can use PJL commands to get and set printer preferences.  This includes getting the page count, setting the serial number, and changing the LCD display message.

I was recently tasked with evaluating our printer usage to determine if we could save money by removing low-usage printers.  Like many companies, the majority of our printers were HPs, and we were on a tight budget, so something like Papercut was out of the question.  I also wasn’t about to go around to each printer and print out the usage report, nor did I want to enter the Web interface of every printer to manually get this information.

Thankfully, I had already learned how to use PJL commands to set the serial number.  During that time, I also learned that you could get information from the printer using the INFO command.

There are two parts to this.  First, is a script I made that will accept an IP address as an argument and then use telnet to access the printer, run the PJL command, and then print the output back to the terminal.

The most basic of scripts would look like this:

 { echo -e "\033%-12345X@PJL";
 echo -e @PJL INFO PAGECOUNT;
 echo -e "\033%-12345X";
 sleep 5; } | telnet ${1} 9100 | sed -e 's/\r$//'

This will run the PJL commands using the escape character when you pass an IP address as a first argument to the script.  You could also just replace the ${1} with an IP address, but it’s nice to have it a bit more versatile.

The PJL commands use a special escape character which initially gave me a big headache until I figured out how to enter it on a Mac.  I have learned (thanks to od -bc) that this is just ASCII code 033, so I added that into the script to make it more copy/pasteable.  So the script:

  • echo‘s the commands I want to run
  • pipes them into telnet using the first argument passed to the script–which will be the IP address of the printer–using port 9100
  • removes the carriage return characters via sed
  • sleeps for a few seconds to ensure the output is displayed

This will result in some output like this:

Trying 10.20.10.201...
Connected to someprinter.
Escape character is '^]'.
@PJL INFO PAGECOUNT
3733

I ran this once a month and and then compared the page counts to see how often it was being printed to.

If you wanted to reset the counter to zero after each month, you could also do that by adding in this command:

@PJL SET PAGES=0

In my case, it was more important to know the lifetime usage of the printer since most printers had been around for a decade or more.

Using Dropbox For An Easy Restore Of All Your Computer’s Settings

Just to be clear, Dropbox isn’t backup software; it’s a syncing service.  If you delete a file and that change is synced, and your file no longer exists.

I really love the things you can do with Dropbox.  And since I’m stingy, I wanted to use Dropbox for backing up–and more importantly–restoring my computer.

One thing I always hated about getting a new computer was losing all of the customizations and settings that accrued over time.

Before this little trick,

I would spend an entire day re-configuring my computer to get it back to the way it was.

Continue reading “Using Dropbox For An Easy Restore Of All Your Computer’s Settings”

Merge PDFs Natively With A Right-Click In OS X

UPDATE: If you installed this script today (2016-08-15), you may need to update it.  I added a line in the script that should prevent duplicate pages from being appended.

There are plenty of apps that help you merge PDFs into a single file, but if you want something faster with a “native” feel, you can set up an OS X service to quickly merge selected PDFs simply by right-clicking them. Continue reading “Merge PDFs Natively With A Right-Click In OS X”

Convert DOCX to PDF Natively With A Right-Click

Microsoft Office for OS X is usually very sluggish and slow.  This is one reason I don’t like working with DOCs or DOCXs in OS X.  Yes, you can easily view the document using QuickLook (pressing the Space bar while the file is highlighted), but if you actually want to open the file and manipulate it, you need to either buy Office, or get an open source alternative.

Download a pre-built workflow (or create your own by following the steps below).

Continue reading “Convert DOCX to PDF Natively With A Right-Click”

OS X Accessibility Command Line Tool Available On Homebrew

I’m happy to announce that tccutil.py is now available on Homebrew.  A tool for modifying access to assistive devices from the command line.  You can install it like this:

brew install tccutil

The real tccutil (designed by Apple’s engineers), found in /usr/bin, only has one feature: to reset the services (tccutil: Usage: tccutil reset SERVICE).  From a system administrator’s perspective, this is very restricting. Continue reading “OS X Accessibility Command Line Tool Available On Homebrew”

How I Went Paperless And Clutter-free For $32

Ever since I discovered Dropbox, I felt weighed down by the clutter of physical documents.  I use it for all of my digital documents.  After a while, physical documents and pieces of paper began to get on my nerves.  It was much easier to have searchable PDFs that I could access anywhere.  To that end, I wanted to be able to convert any physical document I received into a searchable PDF.  See the video below for the entire workflow in action. Continue reading “How I Went Paperless And Clutter-free For $32”

Block Millions Of Ads Network-wide With A Raspberry Pi-hole 2.0

Update 2016-04-24 : Please note this guide is now out-date, and it is recommended that you use the automated install to install and update Pi-hole.  

Technically, this guide will still work, but it does not include any of the features and improvements that have been added.  This article will, however, still give you some insight into how the Pi-hole functions.

Continue reading “Block Millions Of Ads Network-wide With A Raspberry Pi-hole 2.0”