You can obtain a PDF copy of the C99 standard (ISO/IEC 9899:1999) from ANSI (and other fine standards organizations) for your private use for a modest fee - I believe it was 18 USD when I bought mine. Having that available is invaluable to me. But if you find a copy in public, then it is contraband.

You can find final committee drafts and current working documents of the C (C0x) Standard Committee at the JTC1, SC22, WG14 web site at the Open Standards Organization. (That's Joint Technical Committee 1, Sub-Committee 22, Working Group 14, I believe).

There is also a hardback book 'The C Standard: Incorporating Technical Corrigendum 1' (also including the Rationale) available for a slightly less modest 85 USD or thereabouts.

One of the best books about C is 'C: A Reference Manual' in its fifth edition. However, you asked for 'ultimate official source of standard C knowledge', and the only 'official' such source is the C standard, plus its corrigenda.

See also the material at http://www.coding-guidelines.com/ and http://c0x.coding-guidelines.com/.

Answer from Jonathan Leffler on Stack Overflow
🌐
DevDocs
devdocs.io › c
DevDocs — C documentation
C API documentation with instant search, offline support, keyboard shortcuts, mobile version, and more.
🌐
Microsoft Learn
learn.microsoft.com › en-us › cpp › c-language
C docs - get started, tutorials, reference. | Microsoft Learn
C programming reference for users of Microsoft C/C++ and Visual Studio.
Discussions
Is there something like the official C documentation? - Stack Overflow
I'm looking for the documentation of all the syntax and built-in functions in C, but I can't find any site online which seems like an ultimate official source of standard C knowledge. Apart from the More on stackoverflow.com
🌐 stackoverflow.com
C Documentation
The classic book is "The C Programming Language" often referred to as K&R after the initial of the authors. It is getting rather dated, but is a fantastic book and the only one I found particularly valuable. My advice is to write code, lots of code. Find a problem you have, an annoyance, write some code to solve it. Run into problems, google lots, fall in love with stackoverflow, fix the problem, find more. Programming really is a trade, you learn by doing. More on reddit.com
🌐 r/C_Programming
14
8
March 17, 2023
C Reference Documentation

I like it, but I wish it would not mix, or at least make separate C89/C99/C11 language features.

More on reddit.com
🌐 r/C_Programming
9
32
April 5, 2014
What can you actually do in C?
Things that you can actually do in C : - Embedded and real time programming - GUI programming (GTK, Nuklear, NAppGui, RayGui) - Berkeley Sockets programming - IOT Network programming (ZeroMQ, RabbitMQ, libcurl, Paho MQTT client, nanomsg ) - Talking to databases (Postgresql, sql, sqllite, mariadb, mongodb and more) - WebFrameworks / Web servers (onion, libmicrohttpd, Kore, facil) - Graphics (OpenGL, SDL, RayLib, CSFML) - Command line tools - Command line tools with a graphical interface (ncurses. not curses) - Scientific / Numerical computing / Plotting (GSL, GnuPlot, FFTW, apophenia, libBlas, ATLAS and more) - Machine learning ( FANN, DarkNET). - Crypto ( openSSL, libsodium) - File processing ( jsonC, Libcsv) -Linux / BSD Kernel space programming (drivers e.t.c.) And much much more (compression,encoding, video playback, image processing ....). To further understand the scope of exactly what you can do with C, Just have a look at the following 5 Awesome C lists on the web that include C libraries, applications, editors, build systems e.t.c.: Awesome C - inputsh Awesome C - project awesome Awesome C - oz123 Awesome C - mazurov Awesome C - uhub More on reddit.com
🌐 r/C_Programming
134
98
April 11, 2023
Videos
06:02
🌐 YouTube
Using DevDocs for C Programming: A Must-Have Resource (With Feedback ...
January 24, 2025
04:43
🌐 YouTube
C Programming for Beginners: Understand the Basic Program Structure!
April 3, 2025
🌐 youtube.com
C Programming & Beyond Part 11: Where & How to Read C ...
10:01
🌐 YouTube
Reference Documentation In C++ | C++ Full Course From Scratch - ...
February 18, 2025
02:28:08
🌐 YouTube
Autodoc Tool in C - YouTube
January 28, 2026
04:08
🌐 YouTube
Embedded C Programming Style: Manual
April 17, 2022
View all
View all
🌐
Reddit
reddit.com › r/c_programming › is there any official documentation of c programming
r/C_Programming on Reddit: is there any official documentation of C programming
January 19, 2023 -

maybe some of you will say that the C programming language book is the best but is there any documentation official .

Top answer
1 of 4
67
The "official" documentation for the C programming language is the ISO Standard . You can purchase it there, or from another standards organisation (which might be cheaper!). Or you can instead consult one of the freely-available "draft" specifications instead. The latest of these is N3054 . This should include everything that will be in the upcoming C23 standard.
2 of 4
42
https://en.cppreference.com/w/c
🌐
James Madison University
w3.cs.jmu.edu › buchhofp › class › cs361_s18 › documentation_examples.html
C documentation examples
Input: an array of unsigned integers and its size Output: none, but array will be sorted at the end */ void sort(unsigned int numbers[], int size) { int i; // counter int j; // counter int min_index; // holds the index of the minimum value unsigned int temp; // used for swapping for (i = 0; i < size-1; i++) { // iterate over array elements min_index = i; // set minimum to current index for (j = i+1; j < size; j++) { // iterate over remaining elements if (numbers[j] < numbers[min_index]) { // compare values at positions // j and min_index min_index = j; // if smaller, remember the // index } } temp = numbers[i]; // swap the current index with the numbers[i] = numbers[min_index]; // minimum's numbers[min_index] = temp; } }
🌐
Stack Overflow
stackoverflow.com › questions › 4233925 › is-there-something-like-the-official-c-documentation
Is there something like the official C documentation? - Stack Overflow
Top answer
1 of 11
47

You can obtain a PDF copy of the C99 standard (ISO/IEC 9899:1999) from ANSI (and other fine standards organizations) for your private use for a modest fee - I believe it was 18 USD when I bought mine. Having that available is invaluable to me. But if you find a copy in public, then it is contraband.

You can find final committee drafts and current working documents of the C (C0x) Standard Committee at the JTC1, SC22, WG14 web site at the Open Standards Organization. (That's Joint Technical Committee 1, Sub-Committee 22, Working Group 14, I believe).

There is also a hardback book 'The C Standard: Incorporating Technical Corrigendum 1' (also including the Rationale) available for a slightly less modest 85 USD or thereabouts.

One of the best books about C is 'C: A Reference Manual' in its fifth edition. However, you asked for 'ultimate official source of standard C knowledge', and the only 'official' such source is the C standard, plus its corrigenda.

See also the material at http://www.coding-guidelines.com/ and http://c0x.coding-guidelines.com/.

2 of 11
29

There is this online website devdocs

They have multiple API documentations which are well organized. It is free and open-source.

For c doc click this link http://devdocs.io/c/

🌐
Nus-cs1010
nus-cs1010.github.io › 2223-s1 › documentation.html
C Documentation Guide - CS1010 Programming Methodology
If a parameter is passed by reference to be modified inside the function, we will document it as @param[out]. For a parameter that is meant to serve both purposes (pass a value into the function, be modified, and passed the new modified value out), we use @param[in,out]. The comments should be placed before a file, a function, or a variable that you want the comment to apply to.
🌐
GitHub
github.com › learnwithfair › c-programming-documentation
GitHub - learnwithfair/c-programming-documentation: c-programming-documentation [learnwithfair, Learn with fair, Rahatul Rabbi, Md Rahatul Rabbi ,rahatulrabbi] · GitHub
Comments in C are used to provide explanations or descriptions within the code. They are ignored by the compiler and serve as documentation for programmers.
Author   learnwithfair
Find elsewhere
🌐
GNU
gnu.org › software › gnu-c-manual › gnu-c-manual.html
The GNU C Reference Manual
This is a reference manual for the C programming language as implemented by the GNU Compiler Collection (GCC). Specifically, this manual aims to document:
🌐
Microsoft Learn
learn.microsoft.com › en-us › cpp
Microsoft C/C++ Documentation | Microsoft Learn
Learn how to use C++, C, and assembly language to develop applications, services, and tools for your platforms and devices.
🌐
Vercel
c-language-documentation.vercel.app
C Language Documentation Page
We want to get you as quickly as possible to the point where you can write useful programs, and to do that we have to concentrate on the basics; variables and constants, data types, declarations, operators, statements, and loops.
🌐
W3Schools
w3schools.com › c
C Tutorial
Create Variables Format Specifiers Change Values Multiple Variables Variable Names Real-Life Examples Code Challenge C Data Types
🌐
GitHub
github.com › darshan45672 › C-Programs-Complete-Guide-and-Documentation
GitHub - darshan45672/C-Programs-Complete-Guide-and-Documentation · GitHub
Before we can begin to write programs in C, it would be intresting to find out what really is C, how it came into existence and how does it compare with other programming languages. In this chapter, we would briefly outline these issues. Four important aspects of any languages are - the way it stores the data, how it accomplishes input and output, and how it lets you control the sequence of execution of instructions in a program.
Author   darshan45672
🌐
GeeksforGeeks
geeksforgeeks.org › c language › c-programming-language
C Programming Tutorial - GeeksforGeeks
2 weeks ago - Unlike other programming languages that have automatic error handling, In C language error handling is to be manually done by the developers using error-handling methods, debugging strategies, and functions like perror(), strerror(), etc.
🌐
W3Schools
w3schools.com › c › c_ref_reference.php
C Reference Documentation
This section contains a C reference documentation.
🌐
Cppreference
cppreference.com
cppreference.com
Create account · Log in · Main Page · Discussion · Read · View source · View history · From cppreference.com · Support us · Recent changes · FAQ · Offline version · What links here · Related changes · Upload file · Special pages · Printable version ·
🌐
Cppreference
en.cppreference.com › w › c › language.html
C language - cppreference.com
This is a reference of the core C language constructs.
🌐
Reddit
reddit.com › r/c_programming › c documentation
r/C_Programming on Reddit: C Documentation
March 17, 2023 -

I'm currently learning the great C programming language. So far, my experience with the language has been excellent. I started with CS50 and now I'm just googling stuff about C. Recently, I found a C documentation on GNU's website, however I don't know if it's good enough of a documentation for a novice like me. Do you guys know any better documentation? Any advise would be appreciated.

Top answer
1 of 5
14
The classic book is "The C Programming Language" often referred to as K&R after the initial of the authors. It is getting rather dated, but is a fantastic book and the only one I found particularly valuable. My advice is to write code, lots of code. Find a problem you have, an annoyance, write some code to solve it. Run into problems, google lots, fall in love with stackoverflow, fix the problem, find more. Programming really is a trade, you learn by doing.
2 of 5
7
The K&R book is a classic, but Beej's guide is good too: https://beej.us/guide/bgc/html/split/index.html
🌐
Northern Illinois University
faculty.cs.niu.edu › ~winans › notes › docStandards.shtml
C and C++ Documentation Standards
August 26, 2019 - You can put your documentation in the .h or .c files but NOT BOTH. Never replicate anything!
🌐
Microsoft
microsoft.com › en-us › research › wp-content › uploads › 1998 › 01 › pal-manual.pdf pdf
The C-- Language Reference Manual Simon Peyton Jones Thomas Nordin Dino Oliva
and is acquainted with computers should be able to write her/his own C-- programs after reading this · document. 2 · Syntax definition · The syntax of C-- is given in Figures 1 and 2. 2.1 · General · A C-- program file is written in eight bit ASCII characters.
🌐
Sphinx
sphinx-doc.org › en › master › usage › domains › c.html
The C Domain — Sphinx documentation
The C domain (name c) is suited for documentation of C API.
Related queries
c documentation iso
best c documentation
c documentation reddit
c documentation download
c documentation style
c documentation pdf
c++ documentation generator
c documentation w3schools