std::feof

 

C++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Diagnostics library

Memory management library

Metaprogramming library (C++11)

General utilities library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Strings library

Text processing library

Numerics library

Date and time library

Input/output library

Filesystem library (C++17)

Concurrency support library (C++11)

Execution control library (C++26)

Technical specifications

Symbols index

External libraries

 

Input/output library

I/O manipulators

Print functions (C++23)

C-style I/O

Buffers

basic_streambuf

basic_filebuf

basic_stringbuf

basic_spanbuf (C++23)

strstreambuf (C++98/26*)

basic_syncbuf (C++20)

Streams

Abstractions

ios_base

basic_ios

basic_istream

basic_ostream

basic_iostream

File I/O

basic_ifstream

basic_ofstream

basic_fstream

String I/O

basic_istringstream

basic_ostringstream

basic_stringstream

Array I/O

basic_ispanstream (C++23)

basic_ospanstream (C++23)

basic_spanstream (C++23)

istrstream (C++98/26*)

ostrstream (C++98/26*)

strstream (C++98/26*)

Synchronized Output

basic_osyncstream (C++20)

Types

streamoff

streamsize

fpos

Error category interface

iostream_category (C++11)

io_errc (C++11)

 

C-style I/O

Types and objects
FILE fpos_t	stdinstdoutstderr
Functions
File access fopen freopen fclose fflush fwide setbuf setvbuf Direct input/output fread fwrite Unformatted input/output fgetcgetc fgets fputcputc fputs getchar gets (until C++14) putchar puts ungetc fgetwcgetwc fgetws fputwcputwc fputws getwchar putwchar ungetwc Formatted input scanffscanfsscanf vscanfvfscanfvsscanf (C++11)(C++11)(C++11)     wscanffwscanfswscanf vwscanfvfwscanfvswscanf (C++11)(C++11)(C++11)	Formatted output printffprintfsprintfsnprintf (C++11) vprintfvfprintfvsprintfvsnprintf (C++11)     wprintffwprintfswprintf vwprintfvfwprintfvswprintf File positioning ftell fgetpos fseek fsetpos rewind Error handling clearerr feof ferror perror Operations on files remove rename tmpfile tmpnam

 

Defined in header <cstdio>
int feof( std::FILE* stream );

Checks if the end of the given file stream has been reached.

Parameters

stream

-

the file stream to check

Return value

Nonzero value if the end of the stream has been reached, otherwise ​0​.

Notes

This function only reports the stream state as reported by the most recent I/O operation, it does not examine the associated data source. For example, if the most recent I/O was a std::fgetc, which returned the last byte of a file, std::feof returns zero. The next std::fgetc fails and changes the stream state to end-of-file. Only then std::feof returns non-zero.

In typical usage, input stream processing stops on any error; feof and std::ferror are then used to distinguish between different error conditions.

Example

Run this code

#include <cstdio>
#include <cstdlib>
 
int main()
{
    int is_ok = EXIT_FAILURE;
    FILE* fp = std::fopen("/tmp/test.txt", "w+");
    if (!fp)
    {
        std::perror("File opening failed");
        return is_ok;
    }
 
    int c; / Note: int, not char, required to handle EOF
    while ((c = std::fgetc(fp)) != EOF) / Standard C I/O file reading loop
        std::putchar(c);
 
    if (std::ferror(fp))
        std::puts("I/O error when reading");
    else if (std::feof(fp))
    {
        std::puts("End of file reached successfully");
        is_ok = EXIT_SUCCESS;
    }
 
    std::fclose(fp);
    return is_ok;
}

Output:

End of file reached successfully

See also

eof	checks if end-of-file has been reached (public member function of std::basic_ios<CharT,Traits>)
clearerr	clears errors (function)
perror	displays a character string corresponding of the current error to stderr (function)
ferror	checks for a file error (function)
C documentation for feof

Follow Lee on X/Twitter - Father, Husband, Serial builder creating AI, crypto, games & web tools. We are friends :) AI Will Come To Life!

Check out: eBank.nz (Art Generator) | Netwrck.com (AI Tools) | Text-Generator.io (AI API) | BitBank.nz (Crypto AI) | ReadingTime (Kids Reading) | RewordGame | BigMultiplayerChess | WebFiddle | How.nz | Helix AI Assistant