File input/output

The <stdio.h> header provides generic file operation support and supplies functions with narrow character input/output capabilities.

The <wchar.h> header supplies functions with wide character input/output capabilities.

I/O streams are denoted by objects of type FILE that can only be accessed and manipulated through pointers of type FILE*. Each stream is associated with an external physical device (file, standard input stream, printer, serial port, etc).