How will you print any character, string or value of a variable without library functions in C?

Question

If for example I should not use standard library functions like printf(), putchar() then how can I print a character to the screen?

Is there

Answer 1

In standard C, you can't. The only I/O defined in C is through the C standard library functions.

On a given platform, there may be ways to do it:

• Make kernel calls directly. You will probably need to write some inline assembly to do this. You could make litb's write call directly, without using your C library. Grab the source of your C library to see how it's done.
• Write directly to the frame buffer. Multi-user OS's often disallow this (at least without making any library/kernel calls).

Unless you're writing your own C library, I'm not sure why you'd want to do this.