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From: ado@elsie.UUCP
Newsgroups: net.unix-wizards
Subject: Re: kernel recognizing #! scripts
Message-ID: <833@elsie.UUCP>
Date: Fri, 9-Mar-84 15:52:52 EST
Article-I.D.: elsie.833
Posted: Fri Mar  9 15:52:52 1984
Date-Received: Sat, 10-Mar-84 12:48:50 EST
References: <117@ios.UUCP>
Organization: NIH-LEC, Bethesda, MD
Lines: 19


	One advantage to having the kernel recognize #! scripts is
	that set-uid/gid mode works.  Just as with a binary, the
	kernel recognizes this mode and starts the shell or whatever with
	appropriate effective uid/gid.  On 4.1bsd, scripts without
	#! ignore set-uid mode. . .
		Rich Altmaier, Integrated Office Systems.
		decwrl!ios!richa

Note, however, that in a binary program you can issue a system call to
reset the user (or group) id to the "real" (as distinct from the effective) id.
I've yet to learn of a way to do this in shell scripts.  Maybe the unavailable
korn shell supports it.
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