Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!uw-beaver!rice!sun-spots-request
From: sunloop!oconnor!porsche!miker@central.sun.com (Mike Raffety)
Newsgroups: comp.sys.sun
Subject: Re: "Best Way" to inhibit halting of workstations
Keywords: SunOS
Message-ID: <8904211638.AA22065@porsche>
Date: 5 May 89 18:15:43 GMT
Sender: usenet@rice.edu
Organization: Sun-Spots
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Approved: Sun-Spots@rice.edu
Original-Date: Fri, 21 Apr 89 11:38:32 CDT
X-Sun-Spots-Digest: Volume 7, Issue 268, message 1 of 21

Brent Chapman ({cogsci,lll-tis,uunet}!capmkt!brent) says:
>  You must do the mv & cp before beginning because the current /etc/init
>  file is "busy" (because the program is running) and can't be modified.

/etc/init is compiled to NOT page (i.e., pure executable), so that you CAN
delete/update it without crashing your system (when it goes to page out of
a non-existent or changed file).

I like the binary patch to /etc/init, but instead of the custom "sq"
program, a simpler solution might be to make a hard (or soft) link called
"sq" (or any other two letter name, to match the space used in /etc/init
for "sh") to /bin/login, which will do just as effective a job of keeping
the machine safe.

Also, if you screw up your /etc/init so that it's unusable, you can use an
undocumented flag to boot, "-i", to specify an alternate version of
/etc/init to use (e.g., /etc/init.orig, like "> b sd(0,0,0)vmunix -i
/etc/init.orig").  Of course, anyone else can, too, so once you've
verified your modification works, delete the unsecure version of
/etc/init.