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function

<cstdio>

feof

int feof ( FILE * stream );

Check end-of-file indicator

Checks whether the end-of-File indicator associated with stream is set, returning a value different from zero if it is.

This indicator is generally set by a previous operation on the stream that attempted to read at or past the end-of-file.

Notice that stream's internal position indicator may point to the end-of-file for the next operation, but still, the end-of-file indicator may not be set until an operation attempts to read at that point.

This indicator is cleared by a call to clearerr, rewind, fseek, fsetpos or freopen. Although if the position indicator is not repositioned by such a call, the next i/o operation is likely to set the indicator again.


Parameters

stream
Pointer to a FILE object that identifies the stream.

Return Value

A non-zero value is returned in the case that the end-of-file indicator associated with the stream is set.
Otherwise, zero is returned.

Example

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/* feof example: byte counter */
#include <stdio.h>

int main ()
{
  FILE * pFile;
  int n = 0;
  pFile = fopen ("myfile.txt","rb");
  if (pFile==NULL) perror ("Error opening file");
  else
  {
    while (fgetc(pFile) != EOF) {
      ++n;
    }
    if (feof(pFile)) {
      puts ("End-of-File reached.");
      printf ("Total number of bytes read: %d\n", n);
    }
    else puts ("End-of-File was not reached.");
    fclose (pFile);
  }
  return 0;
}

This code opens the file called myfile.txt, and counts the number of characters that it contains by reading all of them one by one. The program checks whether the end-of-file was reached, and if so, prints the total number of bytes read.

See also

clearerr
Clear error indicators (function)
ferror
Check error indicator (function)