Remembering Dennis Ritchie

Background

Even a decade after his passing away, Dennis Ritchie’s seminal work in Computer Science remains under the radar. In the early 1970s, at Bell Labs, Ritchie created the Unix Operating System & the C programming language which have shaped modern computing. Since then, the software industry has seen phenomenal growth adding millions of jobs worldwide & Ritchie’s work has been front & center.

The end of an era

It was an October evening twitter feed from Nokia that broke the news about Dennis Ritchie. Ritchie, the inventor of the Unix Operating system & the C programming language, had passed away after a long illness. Robert Pike, his long-time collaborator, confirmed the news on his Google+ page. Tributes trickled in from the industry but there was a sense of disconnect about this unknown star from the world of computing. There were a couple of Ritchie’s pictures from the Bell Labs archives that people saw for the first time on the internet. Few op-eds were written that opined that without Dennis Ritchie there would have been no Steve Jobs. As Unix is the foundational software & C the programming language for several leading operating systems, including Apple macOS & iOS, it was argued that Ritchie’s influence was more profound than the industry had acknowledged.

Unix connecting people

Ritchie retired in 2007 and by then the majority of mobile devices including the Apple iPhone & Samsung Galaxy were running on Unix and its variants. As early as the 1990’s, Unix became the de facto system software for Internet Servers & mobile phone systems that were connecting people on a scale not seen before. This massive connectivity was delivering the benefits of the information age to millions and Ritchie’s work was front & center.

Unix based internet connectivity turned out to be a very stable environment for mass deployment. It was by all accounts a solid operating system that could support all sorts of services & distributed applications. Engineering & Business teams could be located in any part of the world & they could collaborate to build large-scale applications & services. Along with collaboration, came massive gains in productivity as geographically distributed teams were no longer limited to an eight-hour shift.

However, as the world was changing around Internet & mobile communication, Ritchie remained under the radar and though his signature was on every device no one knew him outside the research world.

Unix enabling large scale computing

The biggest impact of Unix was on the phenomenal growth of the software industry in the 80’s & 90’s. Large scale financial systems were made possible in the 80’s & 90’s primarily because of the flexibility of the underlying Unix System software. Likewise, Telecommunications Service providers were able to expand business exponentially by providing fast access to the internet via DSL (Digital Subscriber Line). DSL deployment was a huge success for service providers. Though it was never acknowledged, Unix was the stable foundation upon which complex DSL service deployment capabilities were built.

Large, dedicated applications were more the norm even as late as the 90s. Unix came up with a new paradigm which provided a collection of reusable small modules or building blocks that could be glued (pipelined in Unix jargon) together to create new software applications. At Bell Labs, Ritchie’s colleague Kernighan had demonstrated, that for example, a spellchecker application, could be easily created by connecting following existing Unix modules: sentence splitter, word lowercase converter, alphabetical order word sorter, duplicate word remover, dictionary mismatch finder. The idea is widely accepted now but seemed somewhat arcane then to some of his audience.

Unix economic impact

Unix based large scale computing proved to be an economic catalyst for the world. US GDP increased from $5.5T in 1990 to $9.8T in 2000. It was a period of prosperity marked by low inflation, strong job growth, and surging stock market. The decade also saw significantly low oil prices. According to the US Department of Labor, 3.4 million non-farm jobs were added in 1994 which has remained a record. The software industry accounted for a significant chunk of new jobs though companies mostly hired temporary workers to expand their businesses.

Internationally, countries like India that had an English-speaking technical work force saw a huge surge in new employment. India’s software business grew tenfold in the 90’s and thousands of young men & women found employment in an industry that was going through phenomenal growth. And that growth meant millions of lines of application code that were held together by Unix that provided a flexible & stable system core.

Unix philosophy

Ritchie had a great eye for aesthetics. He took the idea of simplicity and symmetry and applied it very deliberately to systems software design. If the iPhone was a triumph of device design aesthetics, Ritchie had successfully applied the aesthetic principles of modularity, uniformity and symmetry to software design.

Programs need to be modular that focus on doing ‘one thing well.’ The power of Unix came from small programs that worked together. This was a significant departure from special-purpose, one-time monolithic programs that were still the norm in the 80s.

Unix provided a hierarchical file system with a uniform interface to represent machine services & devices (such as printers, terminals, or disk drives). The idea of file system subdirectories that seems so intuitive today was a novel concept in the early days of Unix.

Unix was the first major Operating System to provide on-line documentation and ready access to system source code which created a fraternity of engineers that eventually led to the landmark open source movement.

Just doing what made sense

Ritchie went through this great phase of digital transformation in his characteristic quiet & detached manner. At Bell Laboratories, he continued to shepherd UNIX releases & distributions. Given the transformation his work had brought about, he must have looked back at his long career. In an interview after winning the National Medal of Technology in 2011, Ritchie mentioned that early work on Unix came out of the belief that it was the sensible thing to do. Just doing what made sense was a constant theme in his long career.

Accolades & Disappointments In 1983, Ritchie and Thompson received the Turing Award for “development of generic operating systems theory and specifically for the implementation of the UNIX operating system.” In 1999, Thompson and Ritchie jointly received the National Medal of Technology from President Bill Clinton for co-inventing the UNIX operating system and the C programming language. However, there were also disappointments and false starts along the way.

Inferno, a distributed operating system from Bell Labs that Ritchie worked on did not live up to its promise and the project was eventually abandoned. CP-1 (Communication Platform 1), an OSI (Open System Interconnection) standards-based communication stack was launched in the late 1980s & for many years was the talk & the lofty goal of the industry. Ritchie was associated with the project in an advisory role. Industry found OSI cumbersome and inefficient & eventually opted for the more efficient TCP/IP communication.

Legacy

Ritchie was a pioneer of extraordinary creativity and phenomenal work capacity. It is estimated that during Unix development at Bell Labs, he contributed close to 100, 000 lines of code in a single year. He knew the worldwide opportunities his seminal work was creating in computing, but he never took his eyes off the essential task of keeping Unix releases clean & easily accessible. For a very long time, the manual pages of Unix utilities listed him as the person responsible for code maintenance. Though he was a celebrity, for any issues with Unix the buck stopped with him.

His humility & self-effacing personality made it possible for a small team to achieve extraordinary results in a short time. Now that is a far cry from the self-focus that industry leaders often get trapped in pursuing short-term gains. For Ritchie, adding long term value to Bells Labs research never took a backseat.

Ritchie remained anchored to the Bell Labs culture of openness & teamwork. He spent most of his life in Berkley Heights, which is just across the road from Murray Hill where he worked. His high school, Summit High School, was a short distance from his home. He was an intensely private person, but his kindness & sweetness of disposition has often been talked about by his colleagues & family.

I saw him just once in his office glued to the terminal with sunlight streaming behind him. It was summertime on Mountain Avenue, Murray Hill, NJ. I am sure in his mind he knew the blue skies and the gleaming dogwood outside his window. I wish Ritchie had travelled more. He would have really appreciated the respect & affection that people had for him. In High schools in India & other parts of the world, as young boys & girls get ready to take their first programming class, they would be clutching his book, The C Programming Language. Obviously, folks on the street had not heard about him, but their shiny smartphones carried his work & legacy.