Visual Studio 6.0

Tests for end-of-file.

int _eof( int handle );

Function Required Header Optional Headers Compatibility
_eof <io.h> <errno.h> Win 95, Win NT

For additional compatibility information, see Compatibility in the Introduction.


LIBC.LIB Single thread static library, retail version
LIBCMT.LIB Multithread static library, retail version
MSVCRT.LIB Import library for MSVCRT.DLL, retail version

Return Value

_eof returns 1 if the current position is end of file, or 0 if it is not. A return value of –1 indicates an error; in this case, errno is set to EBADF, which indicates an invalid file handle.



Handle referring to open file


The _eof function determines whether the end of the file associated with handle has been reached.


/* EOF.C: This program reads data from a file
 * ten bytes at a time until the end of the
 * file is reached or an error is encountered.
#include <io.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
void main( void )
   int  fh, count, total = 0;
   char buf[10];
   if( (fh = _open( "eof.c", _O_RDONLY )) == - 1 )
        perror( "Open failed");
        exit( 1 );
   /* Cycle until end of file reached: */
   while( !_eof( fh ) )
      /* Attempt to read in 10 bytes: */
      if( (count = _read( fh, buf, 10 )) == -1 )
         perror( "Read error" );
      /* Total actual bytes read */
      total += count;
   printf( "Number of bytes read = %d\n", total );
   _close( fh );


Number of bytes read = 754

Error Handling Routines, Low-level I/O Routines

See Also   clearerr, feof, ferror, perror

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