C Programming Language | Brian Kernighan and Lex Fridman

Full episode with Brian Kernighan (Jul 2020): • Brian Kernighan: UNIX,...
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Brian Kernighan is a professor of computer science at Princeton University. He co-authored the C Programming Language with Dennis Ritchie (creator of C) and has written a lot of books on programming, computers, and life including the Practice of Programming, the Go Programming Language, his latest UNIX: A History and a Memoir. He co-created AWK, the text processing language used by Linux folks like myself. He co-designed AMPL, an algebraic modeling language for large-scale optimization.
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[@Aaronb2245]

C Programming Language 1st/2nd Edition by Kernighan and Richie is the best programming book I have ever read for learning a language. Masterfully written by the experts!

[@thisguy2973]

It’s so good! It can still be used for someone interested in writing in C.

[@InspiredFortunes]

I'm able to provide myself money and food on the table because of the technology this man has created.

[@intuit13]

Which is

[@DenisovichDev]

Um... Which is?

[@TreeWood]

Which is…

[@davidchandra8722]

You earn those bro

[@diptyprakashswain1121]

Bruhh moment

[@gregskupien]

Holy shit, the legend himself! I love this podcast.

[@waverider1674]

If you are working on programming languages like Python, Perl, Java, Ruby remember those languages are written in c/c++, the databases, webservers are all written in c/c++ and above all the operating system on which your application runs is written in c/c++. So practically without c/c++ virtually no software ever runs

[@armincal9834]

Basically if you know those two languages then you don't need any other language, not because they are perfect or superior to modern languages but because they have existed for decades and most core technologies just happen to have been written in them

[@rusi6219]

Except that C++ is bloated garbage

[@cossco8081]

I literally had a "HE WROTE THAT!?" moment. I gotta go finish up that book man.

[@iamblaineful]

Dennis Ritchie and Brian Kernighan are LEGENDS, thanks for the interview! They are both so humble.....incredible.

[@CraigHollabaugh]

This was great! I'm old enough to have been on this journey, started on a PDP11 with a DECwriter in '78. I also know that Lex is a young man from his questions. Thanks from Colorado.

[@anothermouth7077]

Today's generation would never ever able to comprehend the exciting journey we've witnessed

[@stanleywhitehughes]

@@anothermouth7077 lol ok boomer

[@billowen3285]

@@stanleywhitehughes shut up you give us a bad reputation

[@stanleywhitehughes]

@@billowen3285 yeah whatever, I was just replying to the fatuous statement that I've heard so many boomers recite.

[@dushyantm9579]

He knows the answers to the stupid questions he is asking - he's just asking them for the listeners and wants to hear it from the man.. Do you believe lex would ask - 'what is awk?', 'what is grep?' because he doesn't know the answers.

[@mradminus]

Hi Lex, just want to say thank you so much for your work, amazing people you get to interview!

[@carloc352]

It’s great to hear Kernighan himself. I still have the old edition of his (and Ritchie’s) book. I think C is at the sweet spot between expressiveness and Assembly language: it sort of doesn’t hide the machine level, but still is high level.

[@mohamedlatreche8138]

the best podcast ever

[@quinntolchin3080]

Snoop Dogg tiger belly is entertainment, the lex Fridman podcast can change the course of your though and life through deep insights. Not hating on that podcast but it’s apples and oranges

[@patrickd4468]

Back in my first year, early 1990s, in Comp Science we were told to buy Kernighan & Ritchie C programming reference on day 1 and learn it. Amazing book. Memory cost a lot back then and mastery of arrays, pointers and memory allocation/deallocation ( malloc() ,free() etc. was required. These days the development tools generally take care of this. The Heartbleed bug is an example of what happens when memory allocation is not handled correctly in C. OpenSSL is an example of software library that was written in C and the effect of not managing memory correctly in C syntax in a particular version. Heartbleed bug exploited how a version of OpenSSL was using a malloc() function when responding to a request ..basically memory leakage to a vindictive requestor. When I was doing exams in year 1 they would have marked you down heavily for that mistake. Great book and the impact these guys had on the world is amazing. Another great podcast from Lex

[@motbus3]

Lex get the most incredible people on his podcast. you must listen

[@garryiglesias4074]

A lexical analyzer interviewing B.Kernighan ? How ironic...

[@adityask277]

The legend himself 🙌🙌

[@madezra64]

This video deserves far more views than it has. Brian Kernighan is a true master!

[@thevortexATM]

you touch on just about everything on this channel dude, very awesome :)

[@arghyadeepchatterjee6100]

Without saying anything else....I would just like to say a big THANK YOU to Brian Kernighan. You are the Legend.

[@lunes-1]

Great video,keep it up x!

[@DANISH4114]

That just emotional moment for me man. Listening to the one and only. Really wish his compatriots Mr. Legendary Ritchie ,Mr Thompson were here for some you know one to one. These guy’s are literally father of modern world as we know. No words to describe. Millions of people to come millions to go millions to earn but only these guys will forever be etched into the history.🫡hats off to these guys for achieving this. It’s unbelievable how many people made living and are making it because of them.

[@artukikemty]

A living legend this guy. Thanks for the interview!

[@mirekheikkila756]

i loved c! you could have inline assembly and also use c++ on top of it if you wanted or not!!

[@robertgwatts1858]

I'm just a hobby programmer. But years back I settled on two languages for all my projects; C, which is nice and close to the metal for high performance, yet still very readable, and Common Lisp, where I do all my Unicorn and pumpkin programming. 😁

[@axitc]

"C wears well as one's experience with it grows" ~ The C Programming Language (ANSI Edition)

[@ramankr0022]

I bow down before you and touch your feet, master. I'm reading your book. Give me blessings. 🙏🙏

[@slavko5666]

I started reading that book a few weeks ago

[@Pmc07AyeUrDa]

I think you should have these clips on their own channel. It helps differentiate them from the main channel.

[@maratimus]

Yeah, this man is a legend...

[@TheMinchio]

This is so true about modern programming languages books, The C Programming Language book is even good for non-C languages :P , these guys were just in other level back in those days.

[@madezra64]

I love the of him working for AT&T with his legs kicked up on his desk just casually showing off Unix. These guys knew they knew what they were doing.

[@97leeman]

Lmao omg this is the dude that wrote the book I bought omg thank you

[@user-jg8lx7ss6u]

Lex is awesome. Inviting such great persons which became idols of modern age.

[@sebhacks]

an absolute legend, I hope history remembers him.

[@alefratat4018]

C and awk still get 95% of my stuff done today in 2020. Who needs Python really...

[@chayanroychoudhury3091]

What type of stuff?

[@alefratat4018]

@@chayanroychoudhury3091 All kind of stuff but mostly machine learning, deep learning, computer vision targeting embedded systems.

[@alefratat4018]

@Mr Shikigami What do you mean by slow ? C runtime performance is the best ... Ah, if you mean the algorithm development process by itself: In my case, the actual time sinks are the data processing pipelines, more than the training hyper-parameters / network architecture optimizations, despite what all the fancy frameworks and Auto-ML guru want to make you believe. And to be fair, I am doing deep learning for real use-cases, not to beat the latest ImageNet benchmark by 0.2% accuracy point, so my needs differ quite a lot with those of researchers. So C is a very good language in that case (C++ is OK as well but those long compile times are a productivity killer for me).

[@alefratat4018]

@Mr Shikigami Short answers: 1. the same time and 2. no. I really don't know where you get this idea. To break it down at bit: 1. Overall, C and C++ runtime speed are equivalent, and they are the fastest out there. Faster than Java, way way faster than Python. 2. Now, when considering AI 'training' (the learning process). Nowadays, the heavy lifting is done on the GPU. For that, you use a GPU compute API, Cuda being by far the most popular for deep learning stuff. Cuda kernels can be embedded in C or C++ code. 3. When it comes to AI model deployment (i.e what the end-user actually gets), processing speed is very often crucial and you may not have access to powerful GPUs. In that case, you need to optimize the speed on the CPU. Again C or C++. All the state of the art inference engine are implemented in C or C++, and to be fair, the performances bottlenecks are often coded in assembly (or using specific CPU instruction sets). So, when it comes to speed, C and C++ are perfect tools for AI. C++ is used in majority because it's culturally dominant today. But C is also a very good choice. At the end, most of the AI frameworks have converged towards the same design: low-level code in C/C++ (where the real things happen) and high-level API in python to leverage its convenience. Hope it clears things up a bit.

[@alefratat4018]

@Mr Shikigami Sure, you could use Rust but the Rust AI ecosystem is almost non-existent. Best you can hope is to use some Rust bindings from major frameworks. Depends on what you want to do at the end: if it's just a hobby, you could try Rust. But, as a professional, I would stick with Python and C++. Keep in mind that AI field is quite dense nowadays, with a lot of concepts to wrap his head around. You probably don't want to add on top of that the burden of learning a complex language. That's why Python is that popular, it's a language that is easy to learn and to deal with (relatively).

[@Massenko]

This man is a legend

[@tinfoil8599]

the Pascal (sorry) Report was another book that served as the de-facto standard for its language before there was a formal standard.

[@sanjaybhatikar]

Wonderful! Love from a Python programmer who also writes some C/C++.

[@hemao0o1]

I so agree with him about some of the stupid tutorials these days

[@surman1816]

most beautiful and advanced part of C is declarations

[@richardwagon6433]

I see a class roster in his drawer. Imagine being one of those students. Your school picture is on Lex Fridman's podcast lol

[@dtakamalakirthidissanayake9770]

Whole Computing World Still Sit On The Shoulders Of Legends Dennis Ritchie, Ken Thompson,Brian Kernighan, Linus Torvalds. If You Want To Enjoy The Beauty Of C.Get Hold Of The Book, "The C Programming Language" Is Absolute Must. To Supplement "C A Reference Manual" By Samuel P. Harbison

[@bharathelangovel2260]

Let's not forget, Richard Stallman and those who work on GNU projects as well.

[@dtakamalakirthidissanayake9770]

@@bharathelangovel2260 My apology, I forgot that Legend Richard Stallman, totally. It is him gave birth to Free Software to the world

[@adityaranigaon]

I won't consider Linus to be among this group. James Gosling , Von Rossum , Andres Heljsberg. Those are the people

[@dtakamalakirthidissanayake9770]

@@adityaranigaon LINUX means a lot to a lot of programmers, Therefore Linus Torvarlds

[@adityaranigaon]

@@dtakamalakirthidissanayake9770 True brother. But it was ken Thompson , Dennis Ritchie and all who thought of an OS for programmers. You can't compare Linus with these legends.

[@cloerenjackson3699]

Why does this suddenly end? Why not just upload the whole thing?

[@aberba]

You should try talking to the D programming language guys. Would be nice to watch. Just finished The origin of the D programming language document and it was interesting.

[@dickschwanzstein1789]

I’m more of a fan of the E programming language personally. F is also quite good. Stay away from G though.

[@abdelhaksaouli8802]

Imagine how cool it is to have such man as your grandpa x')

[@code2266]

would ask about pointers instead of fairy tales😜

[@phxrazdan]

I still have the book circa 1986/87

[@londomolari5715]

His comments about examples shows the UNIX way. input | program > output.

[@johnmcginnis5201]

Today we call this ecosystem. C had it first in a way. To think, I still have my K&R C book. Even refer to it from time to time when the ole brain phases out on a topic.

[@mpumi1024]

What does it take to become a distinguished programmer, a principal engineer

[@whatup20eleven]

Me a noob who knows basic syntax and did few exercises and programs prior to reading this book.. ,.......Chapter 1... WTF ..Its like trying to understand Shakespeare but English is ur 2nd language while being aware of your ADHD

[@dickschwanzstein1789]

Haha nice one. I can definitely imagine I would feel the same way

[@humanbeing4556]

Wow, The greatest living legend

[@snippletrap]

The Canadian accent is strong in this one.

[@masteroogway8601]

Parsing integer is pain in c

[@wandersgion4989]

“Forgive the romantic question, but what is the most beautifuuuuul and aluuuring aspect of C?” I bet he says this in the full podcast right?

[@EdgeOfLight]

why does the interviewer sound like he smoked three joints in a row?

[@siddhantjha6649]

Look how small our population is who really appreciate this art...

[@simpliside]

Respect

[@user-zg5ck8rm5z]

C language is mother of many languages like c++,java, javascript etc

[@quantumac]

Retired now, and all my career as a software developer involved writing code in C and C++. I thank Dennis Ritchie and Brian Kernighan for authoring such a well-written and precise text about C. My only gripe involved how they introduced the world to a formatting style where curly-braces are not lined up vertically. The first thing I did whenever I took over a piece of code written by someone who used that style was reformat it. IMHO, it's a hard style to read and it is very error prone. I refuse to use that style, no matter how popular it has become.

[@FinanceWisdomTech]

C programming language the grandfather of them all languages.

[@kermitdafrog8]

Assembly the great grandfather of them all.

[@thedduck]

What about B lang.. or A lang.. or ASM lang.. or a BIN lang?? a great great great great grandmother??

[@nikos4677]

Machine code. The father of all

[@asafcohen3562]

c is still the best of programming language

[@nicogreco6926]

@@redsnflr i think so, until Golang opened the floodgates to more and more features. Many devs I work with, some have been in the business for 20 years believe Golang will go the path of C++ and become a wildly bloated language. Hopefully they are wrong. We have enough bloated features in other popular languages.

[@theucrafter1666]

@@nicogreco6926 what do u mean by a bloated language?

[@asafcohen3562]

@@stephenkamenarNot everyone is a game developer c is a general programming language

[@michaelscarn9970]

Not in industry.

[@thedduck]

Yeah but until Scratch was invented that is

[@JohnSmith-xr4uy]

Oldies but goodies...

[@roccocoyote]

I want a Prolog and Dolphins Episode

[@mobsnitchanonymous213]

The top .90637 percent of podcasts.

[@stutteringcris468]

IT'S TOO HARD!! 😭😭😭

[@sir0nion]

Nothing is too hard if you keep trying.

[@sunray9941]

Лекс, был бы таким хорошим зятем для кавказской мамы. Но уже кольцо наверное на пальце. Не видно.

[@itsvoid2917]

Java.

[@marti.2718]

why does he never look in the eyes and act tough?? like its just cringe idgaf about any replies

[@BakedBanana]

oh

[@2Phast4Rocket]

The opposite of useful programming books are the vast array of useless VHDL programming books that only contain definitions of syntax, devoid of any useful examples. Worse most of the examples of syntax definition could not be run by themselves and you had to string together multiple examples from multiple chapters for a simple VHDL program to run.

[@chipminion7887]

A great guy. I almost forgive him for K&R indentation (which should probably be blamed on the BCPL people anyway).

[@makers_lab]

Yes, and great language in BCPL as well as C of course. I got a BCPL compiler for my BBC micro and co-processor back in the 80's, and I've got fond memories using that for some projects I was working on before later porting onto my Mac+ and lightspeed C at Uni. And the C book was perfect, thin and packed with just what was necessary and no more.

[@DaveWhoa]

Luke ..... I am your Father

[@fademusic1980]

efficienC

[@kdiggity1]

I love C.

[@frenchthomasmusic]

Did I just watch computer nerd p*rn ?!! 😂😉👍

[@koshka02]

#include int main(void) { printf("Hey all"); return (0); }

[@SevenDeMagnus]

Cool

[@NyanCat3333]

Hi

[@hankmmxviii2640]

Did anyone mishear Unix as Linux? I was like wow Linux is ancient...

[@sjorsvanhens]

Python zoomers are gonna hate this

[@ichaa3tech]

He uses it lol .when awk is not enough.

[@thedduck]

Why is that? You have a problem with the snake or something?

[@jadsingh1202]

@SR MTBFF I don't think GO or Rust will replace C language as system programming language, C is much faster.

[@davidjohn3633]

@@jadsingh1202 false. Rust is almost as fast as C. But I think rust will take the place of c++. Golang shouldn't be in the same category of systems programming.

[@TehGettinq]

@@jadsingh1202 C isnt faster than Rust. It just compiles faster and the binaries are smaller (who cares nowadays). Rust is much much much safer. Rust is definitely superior to C. Its as fast, safer and the tooling is better.

[@SnoopyDoofie]

It had its place and time but I find it a tragedy that today it is required to learn in computer science. The number of people who actually use C is very small compared to millions who program in the popular languages of today. Gees, maybe we should have engineers building the mechanical adding machine that Charles Babbage developed back in the 1800s. Or have everyone learn Ada, since it was Ada Lovelace who actually wrote the world's first programming language in the 1800s. Move on folks, for crap sakes.

[@divingradish]

I think, C is required to learn in computer science because, it is a language that is not too low or too high level. It is relatively easy to be read by human and still close enough to machine. That way, you can still learn how machine (computer) works, without dealing with cryptic language like assembly. Popular language today tends to be very high level, that makes programmers don't need to know about how computer works. That's a good thing in software industry, but would be a bad thing in computer science.

[@SnoopyDoofie]

@@divingradish Wrong. In computer science, learn assembly if you need to teach the basics of a computer. Then from there, just move on to a higher popular language.

[@divingradish]

@@SnoopyDoofie Yes, you need to learn assembly if you want to study machine more closely. But if you want to learn basic of programming AND data structure, language like C would be one of the best choice. In C you need to have some knowledge of memory. That's count as learning about machine. Popular languages tends to abstracting that aspect. It's more about the balance of high and low level.

[@SnoopyDoofie]

@@divingradish I've been writing code for 40 years and have covered many languages including assembly and C. I even wrote my first app using a punch card. Today I develop with Kotlin and Javascript. Believe me, you don't need to learn C.

[@tinfoil8599]

@@SnoopyDoofie punch cards, eh? "app"? of course you did, champ. you have strong opinions (and keep in mind you venture into paedagogy of CS territory which is a whole different can of worms over and above which language is"better"), but all you have argument-wise is snark and factually dubious tidbits of information (Ada is a Pascaline language thas nothing to do with Lady Ada Lovelace other than being named after her, for one. No Ada advocate in their right mind would argue that Ada should be taught because it's based on Lady Ada's work). one would have thought your supposed over-9000 years of experience would give you a deeper and more differentiated and refined understanding.

[@Americabeatz]

it literally took me 20 lines with c to solve a problem that i could do with 1 line in python.

[@julianatlas5172]

but that code will run 20 times faster and on 20 times less resources than that python line (generally). That's why C has it's place and python has it's place

[@SammyRunner1]

List comprehensions, Generators and etc.. we have our weapons

[@sharansiva7635]

This really shows how ignorant you are with programming

[@thedduck]

Well I bet it'll only took 1 block in Scratch..

[@Americabeatz]

@@julianatlas5172 oh yeah, instead of taking 2 seconds it will take 3 seconds.

[@tulumataman3233]

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[@mrsadisa6593]

Same here, My portfolio has been going down the drain while I try trading,l just don't know what I do wrong

[@willisaustin4610]

Trading with an expert is the best strategy for newbies and busy investors who have little or no time to monitor trade

[@sebastiancarreras8583]

@Daley Morrow Wow I'm just shock you mentioned and recommended Expert Mrs Karen Charles,I thought I'm the only trading with her

[@maryamsani5088]

​@@sebastiancarreras8583 You don't need to be shock because I'm also a huge beneficiary of expert Mrs Karen

[@feliciaann7366]

I stumbled upon one of her clients testimonies and decided to try her out...I'm Expecting my third cashout in 2days

[@PrivateSi]

I HATE C as much as Unix/Linux and HTML+CSS+JS+SQL from a linguistic perspective.... sure, they get the job done, but via a mixture of terse obfuscation and bloated verbosity... It's certainly not the worst language, but it's nowhere near the ideal computer language for many reasons yet got forced on the world and stopped better competition due to ACADEMIC HEGEMONY spreading to industry. Committees of intellectuals then proceded to bloat and confuse C more and more, until C++ emerged.. C taught me, if you want a job done clearly, cleanly and efficiently don't get professors and students involved.

[@PrivateSi]

@MF Nickster .. C is cobbled together and had fundamental inconsistencies from day 1.. It's because syntactic infection was it's backwards variable declarations (data type :: variable name instead of name first, type second). Horrible, and only a tiny bit easier to compile. Assembly is more consistent (if not between rival assemblers, ie. ATT vs Intel X86 syntaxes).. Operator overloading is a useful and expressive, powerful feature if used sensibly but C++ OO syntax is dreadful, -> . junk..... It's just a pity Pascal had 'begin' and 'end' instead of concise curly brackets like C. Would have been a much better dominant syntax. Python kind of did that with knobs on but 30 years later.

[@PrivateSi]

@MF Nickster .. To me, the procedure and function keywords were acceptable verbosity but the begin and end weren't. At least it got the basics right, such as a sensible pointer system and better object extensions when they were added, and of course, consistent variable declaration syntax and record / object / class definitions. More flexible unit management too, Most pascal compilers also started using c++ extended assignment operators +=, *= etc.. Delphi was far superior to C++ but C++ was the industry standard, unfortunately. Borland compilers were better than MS and most of the competition, including their own C++ Builder compiler until they merged their back-ends via a shared object code system. Delphi crapped all over MS visual C++ and VB in every way, as an IDE and compiler.

[@PrivateSi]

@MF Nickster .. My favourite self-designed for fun, never implemented prog. lang. was called Q++ and was at first limited to only symbol combinations reserved, no keywords (which can be done but it's a little too difficult to read), but then added 2 letter keywords and 3 symbol operators (but I think I ended up sticking to 2, it was 25 years ago. I had a version where scope was only denoted by tab indent, no curly brackets, This was actually the most readable, not just the most concise and easiest to compile. It extended a decent OO class system with an object-relational database extensions. Could do low and high level coding equally well. It was fun to think about for a week as a student, and helpful to get a deeper understanding of langs and compilation of them... --- Blah, blah.. Anyhow my belief has always been a programming language should have an IDE (or at least editor) specification too. One of my favourite 'languages' just used trees with a symbol for the branch or block type, and was used to program process control software onto eproms,but I can't remember the name and have never been able to trace it. Dad used it in his electrical control system job and taught me the basics but I only used it for a small home control project we did together in the end, but it made C seem very verbose, and Pascal (derivatives) like writing a novel.

[@altairbueno5637]

Lmao the interviewer is bad af

[@burkebaby]

I'm able to provide myself money and food on the table because of the technology this man has created.

[@sulfasolate]

Cool