What is the purpose of EOF in the C language?

EOF, an abbreviation for End Of File, is a special constant in the C language that signifies the end of a file.

In the C language, EOF is defined as an integer constant with a value typically of -1. When reading characters from a file, encountering EOF indicates the end of the file has been reached. Similarly, when writing characters to a file, encountering an error or reaching the end of the file results in a returned EOF, indicating a failed writing operation.

EOF is often used in looping through file operations, where it signals the end of the file and stops the loop once reached. Furthermore, EOF can also be utilized to check for errors in file reading or writing, as it will return EOF if the operation fails.