std::clearerr

 

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Defined in header <cstdio>
void clearerr( std::FILE* stream );

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

Parameters

stream

-

the file to reset the error flags for

Return value

(none)

Example

Run this code

#include <cassert>
#include <cstdio>
 
int main()
{
    std::FILE* tmpf = std::tmpfile();
    std::fputs("cppreference.com\n", tmpf);
    std::rewind(tmpf);
 
    for (int ch; (ch = std::fgetc(tmpf)) != EOF; std::putchar(ch)) { }
 
    assert(std::feof(tmpf)); // the loop is expected to terminate by EOF
    std::puts("End of file reached");
 
    std::clearerr(tmpf); // clear EOF
 
    std::puts(std::feof(tmpf) ? "EOF indicator set"
                              : "EOF indicator cleared");
}

Output:

cppreference.com
End of file reached
EOF indicator cleared

See also

feof	checks for the end-of-file (function)
perror	displays a character string corresponding of the current error to stderr (function)
ferror	checks for a file error (function)