Who invented DOS?

willisjo at zianet.com willisjo at zianet.com
Fri Mar 4 10:51:10 CST 2005

vrs writes: 

>> At 09:26 AM 3/4/2005, Jim Leonard wrote:
>> >You could make a case that CP/M was modeled after Unix, but we won't go
> there :-)
>> Never!  RT-11, maybe.
> I always thought both were modeled after OS/8 :-).  (Which was, in turn, a
> souped up DMS.) 
>     Vince 

It was originally written by Tim Patterson of Seattle Computer Products, as 
86-QDOS (Quick and Dirty OS). The initial purchase by Microsoft was for 
$15,000 IIRC, but full rights to the OS were purchased later for a larger 
sum. Patterson was originally planning on including multitasking, but did 
not due to time constraints. The OS gained tree-structured directories and 
I/O redirection/pipes (< > >> |) in 2.0 (inspired by UNIX), and a major 
rewrite for 5.0 (I believe this rewrite was largely the work of Charles 
Simonyi, but could not be sure). 

Tim Patterson was hired by Microsoft for a period of time. 


John P. Willis
Coherent Logic Development 

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