# [OS X TeX] Hyperlink failure with TeXShop and Preview

Peter Dyballa Peter_Dyballa at Web.DE
Sat Feb 10 07:40:06 EST 2007

```Am 10.02.2007 um 08:43 schrieb Bruno Voisin:

> an Apple bug? Or are < and > proscribed in theory in URLs? Is there
> a special way of inputting < and > in hyperlink destinations with
> hyperref that would avoid the above problem?

There are some rules about URLs and other URIs, for example RFC 2396
(http://www.ietf.org/rfc/rfc2396.txt). It defines a set of delimiters:

delims      = "<" | ">" | "#" | "%" | <">

and another set of "unwise" characters:

unwise      = "{" | "}" | "|" | "\" | "^" | "[" | "]" | "`"

And finally there is also a set of reserved characters that have
always a special meaning:

reserved    = ";" | "/" | "?" | ":" | "@" | "&" | "=" | "+" |
"\$" | ","

All these should not or cannot be used as themselves when they are
meant to stand for themselves, they need to be "escaped." And this is
done in HTML as ``%[HEX1][HEX2]´´.

It would be nice if the url or hyperref packages could do the
escaping, too! The url package documents:

% \url{ }   If the argument contains any "%", "#", or "^^", or ends
with
%           "\", it can't be used in the argument to another command.
%           The argument must not contain unbalanced braces.

Obviously it only cares for TeX syntax – and its users have to know
URI or URL syntax!

--
Greetings

Pete

Make it simple, as simple as possible but no simpler.
Albert Einstein