🚀 go-pugleaf

In article <BtxG3C.5v8@solbourne.com> imp@solbourne.com (Warner Losh) writes:

>In article <1992Sep1.235652.17536@murdoch.acc.Virginia.EDU>
>sdm7g@aemsun.med.Virginia.EDU (Steven D. Majewski) writes:
>
>>What are the common ( and FUNCTIONAL, i.e. not just decorative )
>>X-extensions: ?  
>
>There are none, by definition.  Err, that defintion has been changed.
>The only ones that should be functional are the ones that are found in
>the PEM RFC's (1113-1115).  I know of no other common, functional
>ones.  They usually just add information useful later on....
>

I don't know if "functional" is the right word.
I DIDN'T want to use "standard", as by definition, "X" means not defined
in the standard. ( except for rfc's 1113-1115 - thanks for pointing that
out, I missed those. )

But what I wanted is to exclude things like "X-Last-Band-Seen:" , etc. 
and to include things like "X-mailer:" or the headers added by gateway
of other mail-software, like the "X-VMS-To:" that PMDF adds to leave a
trace of what the original user entered address was. 

[ I'm not sure how I feel about things like X-longitude:,X-latitude:,
  X-phone-number: , etc. They may be "canonical" even if not currently
  "functional" in my sense. If they *are* canonical (i.e. semi-standard),
  though, they can  perhaps be *made* to be functional. ]

I could try to say the distinguishing feature is that the X-headers I'm
interested in are those added (and possibly read) by Programs rather than
People, except that they are ALL added by programs. So I have to exclude
those inserted by inclusion in a .[elm]headers file or via an 'edit headers'
command. 

The other related question is, what (if any) X-headers are read and used 
by other programs ( and therefore, are 'functional' ). The standard doesn't
say they cannot be used. Only that they are non-standard and can't be relied
upon to do anything or a particular thing. But are there any gateways that 
recognize a conforming non-standard X-header as 'hints' or some other 
(machine) 'functional' information ? 


- Steve Majewski