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From: henry@utzoo.UUCP (Henry Spencer)
Newsgroups: net.unix-wizards
Subject: Re: Conventional daemons
Message-ID: <6636@utzoo.UUCP>
Date: Mon, 28-Apr-86 13:41:32 EDT
Article-I.D.: utzoo.6636
Posted: Mon Apr 28 13:41:32 1986
Date-Received: Mon, 28-Apr-86 13:41:32 EDT
References: <2177@brl-smoke.ARPA>
Organization: U of Toronto Zoology
Lines: 15

> [Why do daemons open / as stdin/stdout/stderr?]
> The real question was, why open anything? Surely there's
> nothing functionally useful about opening stdin/stdout on
> "/" and it could be a potential hazard if ported...

You have to open *something*, because innocently writing an error message
to stderr could be a disaster if the program got 2 as the descriptor for
an explicit open of some important file.  This is one way of subverting
setuid programs, in fact.

Our daemons open /dev/null for stdin and stdout and a log file for stderr.
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