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     uservd - supply user services


     userv [-daemon]


     uservd is the daemon called by userv to have a task performed under
     different userid while maintaining limited trust between caller and


     There is one optional argument:

     -daemon     Requests that the program daemonise.  If this flag is
                 supplied, uservd will fork and completely detach from the
                 controlling terminal.  If this option is not supplied, uservd
                 will remain in its starting process group and continue to use
                 the supplied stderr stream for any runtime system messages;
                 this is useful for running uservd as a child of init.  Errors
                 detected by uservd itself will be reported via syslog in
                 either case.


     uservd issues diagnostics of various kinds to syslog, with facility
     LOG_DAEMON.  The syslog levels used are:

     debug       Verbose messages about the activity of the userv daemon.

     info        Two log messages about the nature and outcome of each

     notice      Messages about the status of the daemon, including the
                 startup message and the hourly socket check messages.

     warning     If the uservd exits because it believes that it no longer
                 controls the rendezvous socket (ie, its socket has become
                 orphaned), this level will receive messages indicating why
                 the daemon believes this and notifying of its shutdown.

     err         A believed-recoverable error condition was detected by the
                 userv server in itself, the client or the operating system
                 (this includes resource shortages). The uservd will try to

     crit        The uservd detected a non-recoverable error condition after
                 startup and will exit.

     alert       not used.

     emerg       not used.

     The service configuration language has the facility to direct error and
     warning messages to syslog.  The default facility and level is user.err,
     but the author of the configuration file(s) can override this.


     The daemon’s exit code will reflect how well things went:

     0           The daemon was asked to detach itself from the controlling
                 terminal and this appears to have been done successfully.

     1*          The daemon got a SIGTERM or SIGINT and shut itself down.

     2*          The daemon believed that it was no longer the uservd and so
                 exited to clean up.

     3           uservd was started with incorrect arguments.

     4           A system call failure or other environmental problem occurred
                 during startup.

     5*          There was a non-recoverable error after startup; the uservd
                 had to exit.

     6           The daemon was asked to detach itself, but its detaching
                 child died for some unexpected reason.

                 An unexpected internal error, usually caused by a bug in
                 uservd.  This can also occur if an attempt to block signals
                 using sigprocmask fails.

     Outcomes marked * are not possible if the daemon is asked to detach
     itself - these exit statuses will be reaped by init instead and so will
     not usually be logged anywhere.

     The daemon’s per-request children will report the success or otherwise of
     its request in their exit status.  These are not usually be logged unless
     they indicate a serious problem.


     All of the environment variables passed to uservd will be inherited by
     services as part of the default environment.  (If the set-environment
     configuration directive is used, then other system configuration files
     can modify the environment.  Consult the specification.)


     userv(1) init(8)

     Ian Jackson, User service daemon and client specification.


     GNU userv, including this manpage, is Copyright (C)1996-2003,2006 Ian
     Jackson, except that the userv(1) manpage is Copyright (C)2000 Ben Harris
     and Copyright (C)2003 Ian Jackson.

     GNU userv is licensed under the terms of the GNU General Public Licence,
     version 2 or (at your option) any later version, and it comes with NO
     WARRANTY, not even the implied warranty of MERCHANTABILITY or FITNESS FOR
     A PARTICULAR PURPOSE.  See the GNU General Public License for details.

     You should have received a copy of the GNU General Public License along
     with userv, if not, write to the Free Software Foundation, 59 Temple
     Place - Suite 330, Boston, MA 02111-1307, USA.


     uservd was initially written in 1996 by Ian Jackson.  It became GNU
     uservd in 1999, and version 1.0 was released in 2000.