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”

Roll-your-own Anonymizing Email Server

This post isn’t about a specific security breach, but rather a post to educate you on how to better protect your online identity.  The term “anonymize” is used loosely for lack of a better word.

TL;DR

  • Create a unique email address that forwards to your real email for every site you sign up for.
  • Create a unique password for each site you sign up for
  • Don’t reveal your real email address again
  • Make hacker’s work more difficult

Continue reading “Roll-your-own Anonymizing Email Server”

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”

Batch Download All Of GarageBand’s Loops, Jingles, And Sound Effects

GarageBand has a lot of cool loops and sound effects.  If you are a systems administrator, you might be tasked with deploying these sounds and loops so you don’t need to download it onto each computer when GarageBand opens up.  Or maybe you just want to have these effects for your own personal movies or songs. Continue reading “Batch Download All Of GarageBand’s Loops, Jingles, And Sound Effects”

I Made My Own Script To Fill Out Tedious PDF Forms For Me

I often need to fill out a PDF form for requesting medical records.  I have typically done this using Preview since I can use it to digitally sign the form.  But requesting new records after every appointment started becoming tedious–even when doing it digitally.  I also did not want to wait for years and then request the records all at once (because it’s easier to handle large things like this via attrition rather than in bulk).  So I made a script that would fill out PDF forms for me using the information I specified. Continue reading “I Made My Own Script To Fill Out Tedious PDF Forms For Me”