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The C23 edition of Modern C

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belter ◴[] No.41850897[source]
Important reminder just in the Preface :-)

Takeaway #1: "C and C++ are different: don’t mix them, and don’t mix them up"

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jasode ◴[] No.41851693[source]
>Takeaway #1: "C and C++ are different: don’t mix them, and don’t mix them up"

Where "mixing C/C++" is helpful:

- I "mix C in with my C++" projects because "sqlite3.c" and ffmpeg source code is written C. C++ was designed to interoperate with C code. C++ code can seamlessly add #include "sqlite3.h" unchanged.

- For my own code, I take advantage of "C++ being _mostly_ a superset of C" such as using old-style C printf in C++ instead of newer C++ cout.

Where the "C is a totally different language from C++" perspective is helpful:

- knowing that compilers can compile code in "C" or "C++" mode which has ramifications for name mangling which leads to "LINK unresolved symbol" errors.

- knowing that C99 C23 has many exceptions to "C++ is a superset of C" : https://en.wikipedia.org/wiki/Compatibility_of_C_and_C%2B%2B...

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accelbred ◴[] No.41851853[source]
C++ can seamlessly include C89 headers.

The C library headers for libraries I write often include C11/C99 stuff that is invalid in C++.

Even when they are in C89, they are often incorrect to include without the include being in an `extern "C"`.

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1. kccqzy ◴[] No.41852251{3}[source]
Yeah plenty of headers first have `#ifdef __cplusplus` and then they add `extern "C"`. And of course even then they have to avoid doing things unacceptable in C++ such as using "new" as the name of a variable.

It takes a little bit of an effort to make a header work on C and C++. A lot less effort than making a single Python file work with Python 2 and 3.

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2. flohofwoe ◴[] No.41856228[source]
The '#ifdef __cplusplus extern "C" { }' thing only removes C++ name mangling from exported symbols, it doesn't switch the C++ language into "C mode" (unfortunately).