How I can print to stderr in C?

Question

In C, Printing to stdout is easy, with printf from stdio.h.

However, how can print to stderr? We can use fprintf to achieve it

Answer 1

Some examples of formatted output to stdout and stderr:

printf("%s", "Hello world\n");              // "Hello world" on stdout (using printf)
fprintf(stdout, "%s", "Hello world\n");     // "Hello world" on stdout (using fprintf)
fprintf(stderr, "%s", "Stack overflow!\n"); // Error message on stderr (using fprintf)