__sseek
fp->_seek = __sseek;
._seek = __sseek, \
fp->_seek = __sseek;
fp->_seek = __sseek;
if (seekfn != __sseek ||
extern fpos_t __sseek(void *, fpos_t, int);
return ((st.st_mode & S_IFMT) == S_IFREG && fp->_seek == __sseek ?