The <stdio.h> header defines functions for performing input and output.

The current expected behavior of the standard I/O library is to direct stdout and stderr output to a debugger via DbgMessage(), and to read bytes from stdin via the debugger using DbgGetChar(). Attempting to close one of the standard files [stdin/stdout/stderr] is not currently supported.

The functions in stdio.h are all standard libc functions, and are internationally aware, except that when printing floating-point numbers, they do not use a local-sensitive decimal character.