Question

I have a little project in which I named two same name function in two different source file, but while I building the project, the compiler failed with ‘func_name already defined in filename.obj’.

Why could not I have two functions with the same name in two different source files? I thought the function should be local to the source file only if when we declared it in the header file will it become global.

And except for changing the filename, are there any other elegant solution to duplicated function name in the C programming language?

Answer 1

In C, a function has global scope by default. To restrict its scope, use the static keyword to make it private to a the module.

The role of the header file is just to publicize the function along with its signature to other modules.

All global names must (with some caveats) be unique. This makes sense because that name is what is used by the linker to connect a function call to implementation of the function itself.

Names with static and local scope need only be unique within their scope.