也就是说extern有两个作用,第一个,当它与"C"一起连用时,如: extern "C" void fun(int a, int b);则告诉编译器在编译fun这个函数名时按着C的规则去翻译相应的函数名而不是C++的,C++的规则在翻译这个函数名时会把fun这个名字变得面目全非,可能是fun@aBc_int_int#%$也可能是别的,这要看编译器的"脾气...
Since C++ supports function overloading, additional information has to be added to function names (called Name mangling) to avoid conflicts in binary code. 2. Function names may not be changed in C as it doesn't support function overloading. To avoid linking problems, C++ supports the exter...
extern关键字还有一个重要的用途是用于链接C和C++代码。当我们在C++代码中使用extern "C"时,我们告诉编译器按照C语言的规则来链接代码。 例如,如果我们有一个C语言的库文件(比如clib.c),我们可以在C++代码中通过extern "C"来引用这个库。 // clib.c void c_func() { // function definition in C } // ...
在英语口语中,我们可以这样描述extern关键字的这个用途:“The extern keyword allows us to declare a variable or function in one source file that is defined in another. This helps to avoid naming conflicts when the same variable or function name is used in multiple source files.”(extern关键字允许...
intprintf(constchar*format,...);intmain(){printf("I'm learning the use of Extern in C++");} We use theexternkeyword in C++ programming to eliminate this issue. Whenever the C++ compiler finds the code inside theextern "C" {}block, it makes sure that the name of the function remains...
extern "C" forces a function to have external linkage (cannot make it static) See Richard's comment: 'static' inside 'extern "C"' is valid; an entity so declared has internal linkage, and so does not have a language linkage Linkage from C++ to objects defined in other languages and to...
Things that do not work in extern C It becomes obvious that any C++ feature that requires name mangling will not work insideextern C: extern "C" { // Overloading. // error: declaration of C function ‘void f(int)’ conflicts with ...
function,theCfunctionwillneedtousetheextern"C"link thistellsthecompilerspecified,pleasekeep my name, don't give me the link to generate intermediate function name. The following is a standard way: / / in the.H file on the head of
int CFunc2(); ... extern "C" int CFunc2(); // Error: not the first declaration of // CFunc2; cannot contain linkage // specifier. Starting in Visual Studio 2019, when /permissive- is specified, the compiler checks that the declarations of extern "C" function parameters also match....
C C Extern Video Player is loading. PauseNext Unmute Current Time 0:00 / Duration -:- Loaded: 0% Fullscreen이 기사는 C에서extern 키워드를 사용하는 방법에 대한 여러 방법을 보여줍니다. extern 키워드를 사용하여 C의 ...