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From: "MCCORE::THURY@ti-eg.CSNET".UUCP
Newsgroups: mod.computers.vax
Subject: RE: Login command files
Message-ID: <8702130150.AA09286@ucbvax.Berkeley.EDU>
Date: Thu, 12-Feb-87 12:41:00 EST
Article-I.D.: ucbvax.8702130150.AA09286
Posted: Thu Feb 12 12:41:00 1987
Date-Received: Fri, 13-Feb-87 23:09:01 EST
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The ARPA Internet
Lines: 37
Approved: info-vax@sri-kl.arpa

>I've come across two ways of handling login command files, and wonder whether
>anyone knows a reason to prefer (or abhor) one or the other:

>    1. SYS$SYLOGIN is defined to point to a system-wide login command
>    procedure, which is thus invoked for all processes.  LGICMD (in the
>    UAF) for each user is defined to point to the file LOGIN.COM in
>    that user's home directory.

LOGIN.COM in the user's default directory is the default, and need NOT be
specified in SYSUAF's LGICMD field.  See the VMS 4.4 System Manager's Reference
Manual; Page 5-7 to 5-9 for a complete description of the interactions among
SYS$SYLOGIN, LGICMD & LOGIN.COM

>    2. SYS$SYLOGIN is undefined, but LGICMD for *all* users points to
>    the system-wide login command procedure.  A line late in this command
>    procedure checks to see if a user LOGIN.COM exists, and, if so,
>    executes it.

>As far as I can tell, these two methods are superficially equivalent.  Each
>results in both levels of command procedure being executed in the proper
>order, and neither chokes if no user LOGIN.COM is present.

The two are NOT equivalent!  LOGIN.COM can be bypassed if the user adds
the /NOCOMMAND switch to his username when logging in (i.e.
  Username:  SMITH/NOCOMMAND  )

SYS$SYLOGIN cannot be bypassed.  If there is something that absolutely
MUST be executed by every user at login, the SYS$SYLOGIN method (1 above)
is the preferred.  Depending upon the nature of operations on your system
NOT having a SYS$SYLOGIN could introduce a security hole!!

      Regards,
	Denny Thury
	VAX Systems Support
	Texas Instruments, Inc.
	P.O. Box 801 MS 8006
	McKinney, Texas 75069