GCOS field (Was re: Difference among different UNIX versions)

[Guy Harris]

>> Does anyone know what GCOS really stands for and where it came from?
>
>Or what the BSD and AT&T GCOS field formats are?

Yes.  They are both strings of text (preferably printable characters and
blanks) containing no colons.

Few, if any, programs provided by AT&T as part of its releases assume a
particular format for that field; some people appear to think that the
format in the file distributed with S5 releaes - which, as far as I
know, just happens to be a format used by administrators within AT&T for
their own convenience - is some sort of standard.  The only AT&T
convention I know of is the "pri=nnn" stuff at the front, which "login"
uses to set the "nice" value when you log in.  I know of no software
provided with S5 that obliges you to have a GCOS field in the form

	nnnn-Name(nnnn)

(in fact, several of the accounts used, I guess, for "sysadm" in the
S5R3 "passwd" file *don't* use that format).  Nevertheless, I see a lot
postings from non-AT&T sites where they've blindly adopted that format.

The BSD format is described in ADDUSER(8); this, unfortunately, is
actually used by some programs - said programs even make assumptions
about phone numbers and office names!  Basically, leave out commas, and
you can probably put anything there.

The BSD format includes a convention that not all programs necessarily
honor, which means you may not want to use that convention: if the "&"
character appears in the "gecos" field, those programs replace it with
the login name with the first letter capitalized.  This means you
probably want to leave out "&" as well.