编译器是否编译 C++ 中的 header 文件？

Question

like these are two headers files, now does compiler compiles these?

#include<iostream.h>
#include<conio.h>

Answer 1

When any file is included with an #include directive, the compiler processes its contents as if it were part of the source file being compiled

Answer 2

actually it depends.

#include mean that: hey compiler would you please copy content of that file inside this file(in preprocessing stage). after compiler copied content to given file then it will go for compiler now it depends. most compiler by default compiler compile given c++ files but other external functions and classes(for example stl and other third party libraries that not yours) will be find during run(which is dynamic library) the other side of dynamic library is static library which is instead of compiler compile specific files it goes for your dependencies and compile them along your code and put them together in this case programme does not need to find libraries during run which is why i said it depend.

more information about compiler stages here .

more information about dynamic library and stl and dynamic library here .