_eof

Статья
10/16/2008

Tests for end of file (EOF).

int _eof( 
   int fd 
);

Параметры

fd
File descriptor referring to the open file.

Возвращаемое значение

_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, the invalid parameter handler is invoked, as described in Parameter Validation. If execution is allowed to continue, errno is set to EBADF, which indicates an invalid file descriptor.

Заметки

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

Требования

Function	Required header	Optional header
_eof	<io.h>	<errno.h>

For more compatibility information, see Compatibility in the Introduction.

Пример

// crt_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>
#include <share.h>

int main( void )
{
   int  fh, count, total = 0;
   char buf[10];
   if( _sopen_s( &fh, "crt_eof.txt", _O_RDONLY, _SH_DENYNO, 0 ) )
   {
        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" );
         break;
      }
      // Total actual bytes read 
      total += count;
   }
   printf( "Number of bytes read = %d\n", total );
   _close( fh );
}