_IOERR
inline void clearerr(FILE *_p) { _p->_flag &= ~(_IOERR | _IOEOF); }
inline int ferror(FILE *_p) { return _p->_flag & _IOERR; }
#define clearerr(p) ((void)((p)->_flag &= ~(_IOERR | _IOEOF)))
#define ferror(p) ((p)->_flag & _IOERR)
fp->_flag = _IOERR;
fp->_flag |= _IOERR;
fp->_flag |= _IOERR;
fp->_flag |= _IOERR;
iop->_flag |= _IOERR;
iop->_flag |= _IOERR;
return ((iop->_flag & _IOERR) ? EOF : (unsigned char)ch);
iop->_flag |= _IOERR;
iop->_flag &= ~(_IOERR | _IOEOF);
return (iop->_flag & _IOERR);
iop->_flag |= _IOERR;
iop->_flag |= _IOERR;
iop->_flag |= _IOERR;
iop->_flag |= _IOERR;
iop->_flag |= _IOERR;
while (--i >= 0 && !(stream->_flag & (_IOERR | _IOEOF)))
ret = ((stream->_flag & (_IOERR | _IOEOF)) ? EOF : w);
ret = stream->_flag & _IOERR;
iop->_flag &= ~(_IOERR | _IOEOF);
#define clearerr(p) ((void) ((p)->_flag &= ~(_IOERR | _IOEOF)))
#define ferror(p) ((p)->_flag & _IOERR)