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# clearerr

From cppreference.com
< c‎ | io

Defined in header `<stdio.h>` |  |
void clearerr( FILE *stream ); |  |

Resets the error flags and the `EOF` indicator for the given file stream.

### [edit] Parameters

stream | - | the file to reset the error flags for

### [edit] Return value

(none)

### [edit] Example

clearerr resets the EOF indicator

Run this code

    #include <stdio.h>
    #include <stdlib.h>

    int main(void)
    {
        FILE* tmpf = tmpfile();
        fputs("abcde\n", tmpf);
        rewind(tmpf);

        int ch;
        while ((ch=fgetc(tmpf)) != EOF)   /* read/print characters including newline */
              printf("%c", ch);

        /* Test reason for reaching EOF. */
        if (feof(tmpf))          /* if failure caused by end-of-file condition */
        {
           puts("End of file reached");
           clearerr(tmpf);  /* clear eof indicator */
           if (feof(tmpf))
              printf("EOF indicator set\n");
           else
              printf("EOF indicator cleared\n");
        }
        else if (ferror(tmpf))   /* if failure caused by some other error      */
             {
                perror("fgetc()");
                fprintf(stderr,"fgetc() failed in file %s at line # %d\n", __FILE__,__LINE__-16);
                clearerr(tmpf);  /* clear error indicator */
                if (ferror(tmpf))
                   printf("error indicator set\n");
                else
                   printf("error indicator cleared\n");
                exit(EXIT_FAILURE);
             }

        return EXIT_SUCCESS;
    }

Output:

    abcde
    End of file reached
    EOF indicator cleared

### [edit] Example

clearerr resets error indocator

Run this code

    #include <stdio.h>
    #include <stdlib.h>

    int main(void)
    {
        FILE* tmpf = tmpfile();
        fputs("abcde\n", tmpf);
        fclose(tmpf);            /* close temporary file to force error */

        int ch;
        while ((ch=fgetc(tmpf)) != EOF)   /* read/print characters including newline */
              printf("%c", ch);

        /* Test reason for reaching EOF. */
        if (feof(tmpf))          /* if failure caused by end-of-file condition */
        {
           puts("End of file reached");
           clearerr(tmpf);  /* clear eof indicator */
           if (feof(tmpf))
              printf("EOF indicator set\n");
           else
              printf("EOF indicator cleared\n");
        }
        else if (ferror(tmpf))   /* if failure caused by some other error      */
             {
                perror("fgetc()");
                fprintf(stderr,"fgetc() failed in file %s at line # %d\n", __FILE__,__LINE__-16);
                clearerr(tmpf);  /* clear error indicator */
                if (ferror(tmpf))
                   printf("error indicator set\n");
                else
                   printf("error indicator cleared\n");
                exit(EXIT_FAILURE);
             }

        return EXIT_SUCCESS;
    }

Output:

    fgetc(): Bad file descriptor
    fgetc() failed in file main.cpp at line # 11
    error indicator cleared

### [edit] See also

feof | checks for the end-of-file (function) [edit]
perror | displays a character string corresponding of the current error to stderr (function) [edit]
ferror | checks for a file error (function) [edit]
C++ documentation for clearerr

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