isBinary = (c < 32 && c != '\t' && c != '\n' && c != '\r'
&& c != 5 && c != 27); // nominal binary character filter
// excluding CR, LF, tab,DEL and ^E
isBinary = (c < 32 && c != '\t' && c != '\n' && c != '\r'
&& c != 5 && c != 27); // nominal binary character filter
// excluding CR, LF, tab,DEL and ^E