NAME
EOF - end of file or error indicator
LIBRARY
Standard C library (libc)
SYNOPSIS
#include <stdio.h>
#define EOF /* ... */
DESCRIPTION
EOF represents the end of an input file, or an error indication. It is a negative value, of type int.
EOF is not a character (it can't be represented by unsigned char). It is instead a sentinel value outside of the valid range for valid characters.
STANDARDS
C11, POSIX.1-2024.
HISTORY
C89, POSIX.1-1988.
CAVEATS
Programs can't pass this value to an output function to "write" the end of a file. That would likely result in undefined behavior. Instead, closing the writing stream or file descriptor that refers to such file is the way to signal the end of that file.