What are the functions and what is included in the C runtime

Question

So, I'm trying to understand what the C runtime environment is, and I had to go deeper when creating my own kernel.

I realized that you do not need the C runtime to create each C program (as is the case with the kernel). In addition, the runtime provides an interface between the C program and the kernel. Here are my questions:

• So what does the runtime do?

• Does it act only like this interface (so if we implement it ourselves, we don’t need a runtime), or does it have other functions?

• Is the runtime bound in any files when compiling the program?

• Are common type functions printfor scanfpart of a C runtime or library? What features will the runtime provide?

EDIT: I mentioned What is the C Runtime Library? but she does not answer my questions. What I requested is not considered there.

Answer 1

I am going to answer the question from a different perspective: an embedded system without iron without an operating system. In this case, two important functions are performed:

• Uninitialized static variables are set to 0 (section bss)

• Explicitly initialized static variables get their intuitive meaning

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Answer 2

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