MS DOS HIDDEN CODEShort Bytes: The creator of landmark PC operating system CP/M, late Gary Kildall, accused Microsoft of copying his operating system to make MS-DOS. It’s also long-rumored that MS-DOS contains a secret command that prints a legal notice in Gary Kildall’s name. Well, if you can uncover this secret command, consultant Bob Zeidman will pay you $100,000.

Here’s some background history lesson before we talk about the real deal!

How Bill Gates hit the jackpot with MS-DOS?

If we start reading Microsoft’s history, the MS-DOS chapter comes very early. The operating system acts as a foundation of the Microsoft Empire. Bill Gates got his big break in 1980 when he licensed this OS to IBM.

You might know that Microsoft didn’t develop this operating system in-house. Instead, it acquired another operating system named QDOS–Quick and Dirty Operating System. QDOS was developed by SCP’s Tim Paterson, who was later hired by Gates to modify QDOS into MS-DOS.

If you turn more pages of the history, you’ll come across another technology pioneer named the late Gary Kildall. He was the founder of DRI (Digital Research Inc.) and creator of an early PC OS named CP/M.

MS-DOS-powered PCs soon became a huge success and dethroned DRI as the leading maker of operating systems. Later, Kildall contacted IBM and negotiated a higher license fee compared to MS-DOS, offering CP/M on IBM PCs. As a result, more people bought cheaper PC-DOS and Microsoft continued to grow.

Kildall also accused that QDOS and MS-DOS were directly copied from CP/M, infringing his copyright. DRI’s lawyers claimed that their forensic researchers found that MS-DOS infringed DRI’s software.

It’s also rumored that there’s a secret command in MS-DOS that can print a legal copyright notice in Gary Kildall’s name.

Back in 2012, a consultant named Bob Zeidman decided to examine the MS-DOS and CP/M code to find out any instances of copyright violations. He also looked at the binary code of an early MS-DOS version and found nothing. His findings were published in IEEE Spectrum. He has also made the comparison available on his website.

However, after the publication of his article, it was revealed that Zeidman had an open consulting contract with Microsoft in its battle with Motorola. As a result of a lot of pushback, Zeidman has now put up a $200,000 in prize—$100,000 for anyone who can prove (using accepted forensic techniques) that Microsoft copied CP/M’s code and another $100,000 for the one who can find secret Kildall copyright command in MS-DOS.

So, are you ready for some serious digging? Good luck 😉

Did you find this article helpful? Don’t forget to drop your feedback in the comments section below.

Also Read: Donkey.bas: Bill Gates Programmed World’s 1st PC Game In 1981 — Play It Here