Excellent! Now in MKIV how would I encode an opening quote mark American
style? In previous TeX programs it was always ``. The MKIV substitute
\quotation{foo}
is not practical for my application, where the raw input code
may use the ditto mark " for both opening and closing quotes. I am
looking for something in MKIV equivalent to \char92 in plain TeX. On
the unicode table I find the hex value 008013 but I don't know how to
plug that in to a macro that redefines the first occurrence of " to be
that character, and the second occurrence to be hex 000814 etc. I can
write the macro, I just need the expression equivalent to \char that
gives me such characters in MKIV.