ron@topaz.rutgers.edu (Ron Natalie) (04/02/88)
RFC822 which is the specification used for headers in Internet and USENET messages (but not necessarily UUCP mail) allows _ in the local part (to the left of the @). Underscore is a legal charater in an atom and is not required to be quoted (as certain other characters such as period). -Ron
cfe+@andrew.cmu.edu (Craig F. Everhart) (04/04/88)
RFC822 treats ``_'', and several other several punctuation characters, in exactly the same way as it treats, say, alphabetics. These include: !#$%&'*+-/=?^_`{|}~ As to whether a particular mail system will recognize mail addressed to Firstname_Lastname (or, for that matter, ``Firstname.Lastname''), that's up to the particular mail system. Andrew.cmu.edu, for instance, will get mail to me no matter whether it's addressed as any of the following: Craig.Everhart@andrew.cmu.edu Craig_Everhart@andrew.cmu.edu Craig_F._Everhart@andrew.cmu.edu cfe+@andrew.cmu.edu plus a bunch of less-reliable alternatives that presume the absence of conflicting names, e.g.: cfe@andrew.cmu.edu Creg.Everhart@andrew.cmu.edu c.f.everhart@andrew.cmu.edu
per@erix.UUCP (Per Hedeland) (04/11/88)
In article <Apr.1.17.35.54.1988.3117@topaz.rutgers.edu> ron@topaz.rutgers.edu (Ron Natalie) writes: > Underscore is a legal charater in an atom and >is not required to be quoted (as certain other characters such as period). Where does this notion that periods are not allowed in unquoted local-parts come from (I've encountered it in other places as well)? As far as I can understand, RFC822 quite to the contrary explicitly allows this, giving local-part = word *("." word) ; uninterpreted ; case-preserved as the definition. This is even discussed in some detail in para 6.2.4-5. Regards --Per Hedeland per@erix.ericsson.se or ...{mcvax,uunet}!enea!erix!per
cfe+@andrew.cmu.edu (Craig F. Everhart) (04/14/88)
Excerpts from: 11-Apr-88 Re: Are underbars considere.. Per Hedeland@erix.UUCP (735) > Where does this notion that periods are not allowed in unquoted local-parts > come from (I've encountered it in other places as well)? As far as I can > understand, RFC822 quite to the contrary explicitly allows this... First of all, Ron Natalie's message said that periods were illegal in ``atom''s, not in ``local-part''s. He is correct, as are you, but he was talking about an RFC822 atom, and you're talking about an RFC822 local-part. One can also confuse ``phrase'' with ``local-part''. For obscure (perhaps mistaken) reasons, RFC822 allows (unquoted) periods in local-parts but not in phrases, and allows (unquoted) spaces in phrases but not in local parts. ``phrase'' is what's to the left of an angle-bracket address in a header; local-part is what's immediately to the left of an at-sign. Thus, To: Craig Everhart <Craig.Everhart@andrew.cmu.edu> is a legal header on both counts, but To: Craig F. Everhart <Craig Everhart@andrew.cmu.edu> is illegal on both. There were a lot of inertia-based reasons for disallowing spaces in a local-part. Disallowing periods in a phrase is probably an oversight, but we're stuck with it. Another curiosity is that a phrase can't be null in a message header, so the header To: <Craig.Everhart@andrew.cmu.edu> is, strictly speaking, illegal. (When we have to use a return-path (which, if it's a source-route, can require the ``<'' and ``>'' characters) to compose an error message, sometimes we have to generate a non-null phrase to precede them. I used to use the text constant ``dummy'', representing a syntactic dummy, but when people started to take it as a mild insult, I had to change it to ``Message sender''!) Craig Everhart Andrew message system