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0 pointsConst-me6y ago0 comments

I advise you start by writing the library in C++ and then wrap it in C if you need C ABI of the library.

It’s very hard to write correct C code which does IO and supports multithreading. Take a look at Microsoft’s implementation of fprintf, copy-pasted from Windows 10 SDK: https://gist.github.com/Const-me/f1bb320969adde6c79694265ea6... They use RAII to set & revert the locale, and to lock RAM buffer to avoid corruption by another threads. They use C++ lambda for exception handling. They even use C++ template to avoid code duplication between printf and wprintf.

But these C++ shenanigans are not exposed to user, user calls their `printf` (possibly in a code built by C compiler) and it just works.

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huhtenberg6y ago· 2 in thread

> It’s very hard to write correct C code which does IO and supports multithreading

This is just a random unsubstantiated statement. There's nothing particularly "hard" about writing IO libraries that is language-specific. Multithreaded or not.

Const-meOP6y ago

When you do IO and multithreading, functions often need to acquire and release stuff: mutexes or other locks, resources, locales. Even more so in videogames, e.g. OpenGL code often calls glMapBuffer / glUnmapBuffer many thousand times each frame.

The hard part is making sure you release stuff every time you acquire stuff, exactly once. C++ RAII makes it almost trivially simple, but standard C has nothing comparable. When you only targeting gcc and clang can use __attribute__(cleanup) in C, it helps but still it’s more limited and more error prone compared to destructors.

abcd_f6y ago

> The * hard part * is making sure you release stuff every time, exactly once.

Oy vey... you can't be serious. That's rudimentary basics of using any API.

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