#include <stdio.h> int ferror(FILE *stream);
int feof(FILE *stream);
void clearerr(FILE *stream);
int fileno(FILE *stream);
The ferror() function returns a non-zero value when an error has previously occurred reading from or writing to the named stream (see Intro(3)). It returns 0 otherwise.
The feof() function returns a non-zero value when EOF has previously been detected reading the named input stream. It returns 0 otherwise.
The clearerr() function resets the error indicator and EOF indicator to 0 on the named stream.
The fileno() function returns the integer file descriptor associated with the named stream; see open(2).
See attributes(5) for descriptions of the following attributes: