Re: [VCARDDAV] [calsify] Escaping dquote in a parameter value

[Jack <[e-mail]>]

On 20/06/2012 03:56, Cyrus Daboo wrote:
> Hi, As I am sure most people are aware, a double-quote character is
> forbidden to appear in a parameter value in both vCard and iCalendar.
>  Yet there is a need to preserve double-quotes in a parameter value.
> So I am going to propose an extension to the specifications whereby a
> new escape mechanism is introduced solely for the purpose of allowing
>  d-quote in a parameter value in a backwards compatible manner.
>
> My proposal is to use ^ (0x5e) as an escape character, with only the
>  following two sequences allowed:
>
> ^^ - represents a single ^ character ^' - represents a single d-quote
> character
>
> I ruled out use of \ because some parsers erroneously eat that, and
> it would also be tempting to use \" which is definitely not possible
>  because the dquote cannot appear.

However "\" is already specified in RFC2445 as the escape character in
TEXT (4.3.11).

That section specifies that a DQUOTE is not to appear in a TEXT; but it
also specifies that a ";" shall not appear in a TEXT, and then goes on
to specify that a ";" must be escaped thus: "\;". So I read it as saying
(as clearly as anything is said in that document) that a DQUOTE should
be escaped thus: "\"".

-- 
Jack.