6.18.10 clearerr Function

Resets the error indicator for the stream.

Attention: This function is not implemented by MPLAB XC8 for PIC MCUs. It is implemented by all other compilers, but MPLAB XC8 for AVR MCUs has limited support of data streams.

Include

<stdio.h>

Prototype

void clearerr(FILE * stream);

Argument

stream: stream to reset error indicators

Remarks

The function clears the end-of-file and error indicators for the given stream (i.e., feof and ferror will return false after the function clearerr is called).

Example

See the notes at the beginning of this chapter or section for information on using printf() or scanf() (and other functions reading and writing the stdin or stdout streams) in the example code.

/* This program tries to write to a file that is */
/* readonly. This causes the error indicator to  */
/* be set.  The function ferror is used to check */
/* the error indicator. The function clearerr is */
/* used to reset the error indicator so the next */
/* time ferror is called it will not report an   */
/* error.                                        */
#include <stdio.h>

int main(void)
{
  FILE *myfile;

  if ((myfile = fopen("sampclearerr.c", "r")) == NULL)
    printf("Cannot open file\n");
  else
  {
    fprintf(myfile, "Write this line to the file.\n");
    if (ferror(myfile))
      printf("Error\n");
    else
      printf("No error\n");
    clearerr(myfile);
    if (ferror(myfile))
      printf("Still has Error\n");
    else
      printf("Error indicator reset\n");

    fclose(myfile);
  }
}

Example Output

Error
Error indicator reset