_IO_SYSREAD
{ return _IO_SYSREAD (this, buf, size); }
count = _IO_SYSREAD (fp, fp->_IO_buf_base,
count = _IO_SYSREAD (fp, s, count);
count = _IO_SYSREAD (fp, fp->_IO_buf_base,
count = _IO_SYSREAD (fp, fp->_IO_read_end,
count = _IO_SYSREAD (fp, fp->_IO_buf_base,