From owner-freebsd-hackers  Mon Mar 24 21:32:51 1997
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To: hackers@freebsd.org
Subject: A good way to...
Date: Mon, 24 Mar 1997 22:32:45 -0700
From: Warner Losh <imp@village.org>
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OK.  I'm looking for some good code that will drop privs, do some
operation, and the restore privs.

I'm not sure what the best way to do this.  I'm thinking it is
	
	uid_t xxx, yyy;

	xxx = geteuid();
	yyy = getegid();
	seteuid(getuid())
	setegid(getgid())
	<do it> (eg fopen(zzz, "r");)
	seteuid(xxx);
	setegid(yyy);

I think this does what I want to do, but can someone punch some holes
into this before I commit code like this?

Why am I asking this?  It turns out that I'm starting to get reports
of unintended side effects of some of the checkins that I made It
would help if I was able to reproduce the problems here :-(.  At least
some of them should just drop and raise privs "like" this.

This stuff always makes my head spin....

Also, if someone or someones would like to review anything that I do,
please let me know.

Warner