c/c++ 函数的源代码
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/1127328/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
source code of c/c++ functions
提问by mipadi
I wanted to have a look at the implementation of different C/C++ functions (like strcpy, stcmp, strstr). This will help me in knowing good coding practices in c/c++. Could you let me know where can I find it?
我想看看不同 C/C++ 函数（如 strcpy、stcmp、strstr）的实现。这将帮助我了解 c/c++ 中的良好编码实践。你能告诉我在哪里可以找到它吗？
Thanks.
谢谢。
回答by mipadi
回答by jalf
It's worth pointing out that the source code for the C standard library does not necessarily highlight good coding practices. As the standard library, it has a special status where, for example, it can rely on a lot of unspecified or non-portable behavior simply because they know the exact compiler with which it is used.
值得指出的是，C 标准库的源代码不一定突出良好的编码实践。作为标准库，它有一个特殊的地位，例如，它可以依赖许多未指定或不可移植的行为，因为它们知道使用它的确切编译器。
And of course, this only tells you about C coding practices.
当然，这只是告诉您有关 C 编码实践的信息。
That has nothing to do with C++ coding practices, which are very different. Don't treat them as one language. There is no such thing as C/C++. C is a language with its own coding practices and common idioms, and C++ is a separate, independent language which also has its own practices and idioms.
这与 C++ 编码实践无关，它们非常不同。不要将它们视为一种语言。没有 C/C++ 这样的东西。C 是一种语言，有自己的编码实践和常用习惯用法，而 C++ 是一种独立的、独立的语言，也有自己的实践和习惯用法。
Good C code is rarely good C++ code. strcpyand other C library functions are certainlynot good C++ code.
好的 C 代码很少是好的 C++ 代码。strcpy而其他C库函数肯定不是好的C++代码。
回答by Michael Burr
Most compilers provide source code for the library - however that source code is usually rather more complex and convoluted than you might expect.
大多数编译器为库提供源代码 - 然而，源代码通常比您想象的要复杂和复杂。
A good resource for this is P.J. Plauger's book, "The Standard C Library", which can be had pretty cheaply if you go for a used one. The code presented is not always straight-forward, but Plauger explains it quite well (and gives the reasons why it can't always be straight-forward and still follow the standard).
这方面的一个很好的资源是PJ Plauger 的书“标准 C 库”，如果您选择使用过的书，可以很便宜地获得它。所提供的代码并不总是直截了当，但 Plauger 很好地解释了它（并给出了为什么它不能总是直截了当并且仍然遵循标准的原因）。
回答by Pete
Many C standard library functions have source code listings & discussions in The C Programming Language by Kernighan & Ritchie. The discussions are a helpful way of learning more about the specifics of the C language & how functions in the standard library work under the hood.
许多 C 标准库函数在Kernighan & Ritchie 的 The C Programming Language 中有源代码列表和讨论。这些讨论是学习更多关于 C 语言的细节以及标准库中的函数如何在幕后工作的有用方式。
回答by IRBMe
Look at an implementation of the libcstandard C library. To see how a real, popular C library is implemented, try looking at the glibc code. You can access the code using git:
查看libc标准 C 库的实现。要了解真正流行的 C 库是如何实现的，请尝试查看 glibc 代码。您可以使用 git 访问代码：
git clone git://sourceware.org/git/glibc.git
git 克隆 git://sourceware.org/git/glibc.git
As for C++, you can find the glibc++ standard library on one of these mirrors:
至于 C++，您可以在以下镜像之一上找到 glibc++ 标准库：
http://gcc.gnu.org/mirrors.html
http://gcc.gnu.org/mirrors.html
You can also check out uLibc, which will probably be simpler than the GNU library:
您还可以查看 uLibc，它可能比 GNU 库更简单：
http://git.uclibc.org/uClibc/tree/
http://git.uclibc.org/uClibc/tree/
To give you a flavour, here's the strncpyimplementation from uLibc:
为了给你一个味道，这里是uLibc的strncpy实现：
Wchar *Wstrcpy(Wchar * __restrict s1, const Wchar * __restrict s2)
{
register Wchar *s = s1;
#ifdef __BCC__
do {
*s = *s2++;
} while (*s++ != 0);
#else
while ( (*s++ = *s2++) != 0 );
#endif
return s1;
}
回答by IRBMe
回答by Michael van der Westhuizen
You could also have a look at the OpenBSD source tree. Specifically, you want the string subdirectory of libc.
您还可以查看OpenBSD 源代码树。具体来说，您需要libc 的 string 子目录。
回答by Tim Hoolihan
回答by Sinan ünür
About 10 years ago, I read The Standard C Library by Plauger. Thoroughly recommend it.
大约 10 年前，我阅读了 Plauger 的 The Standard C Library。彻底推荐它。
回答by Eric Petroelje
The implementation will vary somewhat from OS to OS, but the GNU/Linux implementation is probably going to be the easiest one to find out there.
不同操作系统的实现会有所不同，但 GNU/Linux 实现可能是最容易找到的。
