[comp.mail.sendmail] Oh no, its the " at " question again ...

steve@mrc-apu.cam.ac.uk (Steve Platt) (03/14/90)

I think I asked this before, but I can't remember if an answer came over...

In UK-sendmail 1.4a, there was a rule that said :-

| R$+ at $+               $1@$2                   " at " -> "@" for RFC 822

The problem is that sendmail/lib/usr/ (pathname in WORLD ORDER!) seems
to be no respecter of spaces and although the above line does work
as intended; translating addresses like "user at site" into "user@site";
it also has the side effect of translating "user@AT.site" (Austria)
into "user@@.site" (nowhere much use!).

In UK-Sendmail 2.1, an attempt to get round this is to escape the spaces:-

| R$+\ at\ $+               $1@$2                   " at " -> "@" for RFC 822

Although this prevents the "AT" domain getting translated it also prevents
the "user at site" translation from occuring, as far as I can see.

Obviously the same result could be obtained by deleting the rule!
SO did someone get it working, perhaps on a different sendmail?

Should anyone worry (I assume that the " at " use is uncommon these days)?

This is all with sunos 4.0.3's own sendmail.
Many thanks for any (possibly repeated) attention you are giving this one.

Steve platt

parmelee@wayback.cs.cornell.edu (Larry Parmelee) (03/14/90)

The "at" -> "@" translation is a pretty old, no longer current
standard, and generally a Bad Thing to do on the Internet these days.
Drop it if at all possible.

If you MUST support this translation, about the only safe way to
do it is to define a Class  consisting of all the mail punctuation
characters, and  change only those "at"s which are not preceeded or
followed  by one of the punctuators.

Define a class "P" of all the punctuation characters:
	CP. : % @ ! ^ = / [ ]

Using class "P", translate "at"s:
	R$*$~Pat$~P$*   $1$2@$3$4

-Larry Parmelee
parmelee@cs.cornell.edu