How does init determine the user to run a daemon as

[Bill Campbell]

On Fri, Sep 23, 2005, Jan M wrote:
>Hi Roger,
>
>Thanks. How does init determine which user to run the daemon as? Is it the
>executable owner?

That depends on how the program is executed.

Programs started by inetd/xinetd specify the user in the appropriate
configuration files.

Programs run on startup from /etc/inittab (on systems that use that), are
started as root, but may well ``su'' to other users or run programs that
are setuid or setgid to another user (e.g.  apache).

Programs may also be run as users from cron, depending on whether the
system is configured to permit users to have their own crontabs.  The
command ``crontab -l -u username'' will normally show the crontab entries
for a particular username.

Programs run with the ``at'' command, if permitted, will run as the user
initiating the job.

Bill
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