loginid vs. uid.

[BURNS,JIM]

in article <9007162005.AA11293 at mindcrf.mindcraft.com>, karish at mindcrf.UUCP says:
	[discussion of what SVID and POSIX do]
> 
>     The point of having separate logname() and getuid() functions is
>     to maintain the login ID and the real UID as separate concepts.

The following are man logname excerpts from 1) SunOs 4.0, and 2)AU/X 1.1
(SVR2):

1)
DESCRIPTION
     logname returns the contents  of  the  environment  variable
     LOGNAME, which is set when a user logs into the system.

Sun Release 4.0   Last change: 9 September 1987                 1

2) man 1 logname says the same thing, while man 3x logname says (in part):

     DESCRIPTION
	  logname returns a pointer to the null-terminated login name;
	  it extracts the $LOGNAME variable from the user's environ-
	  ment.

     BUGS
	  This method of determining a login name is subject to	for-
	  gery.
	   
Interestingly enough, when I do a su - on AU/X, logname and $LOGNAME both
report the account I su'd to, whereas under SunOs, $LOGNAME reports the
account I su'd to, and logname returns the account I su'd from, in
contradiction to its man page. (My .profile and the system's
/local/etc/profile don't do anything strange to $LOGNAME.)

Sequent Dynix apparently doesn't support logname.
-- 
BURNS,JIM
Georgia Institute of Technology, Box 30178, Atlanta Georgia, 30332
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