.\" Copyright (c) 1989 Jan-Simon Pendry
.\" Copyright (c) 1989 Imperial College of Science, Technology & Medicine
.\" Copyright (c) 1989, 1991, 1993
.\" The Regents of the University of California. All rights reserved.
.\" This code is derived from software contributed to Berkeley by
.\" Jan-Simon Pendry at Imperial College, London.
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.\" modification, are permitted provided that the following conditions
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.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\" must display the following acknowledgement:
.\" This product includes software developed by the University of
.\" California, Berkeley and its contributors.
.\" 4. Neither the name of the University nor the names of its contributors
.\" may be used to endorse or promote products derived from this software
.\" without specific prior written permission.
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.\" @(#)amd.8 5.11 (Berkeley) 6/1/94
.\" $Id: amd.8,v 5.2.2.1 1992/02/09 15:11:39 jsp beta $
.Nd automatically mount file systems
.Op Fl t Ar interval.interval
is a daemon that automatically mounts filesystems
whenever a file or directory
within that filesystem is accessed.
Filesystems are automatically unmounted when they
operates by attaching itself as an
server to each of the specified
Lookups within the specified directories
which uses the map defined by
to determine how to resolve the lookup.
Generally, this will be a host name, some filesystem information
and some mount options for the given filesystem.
.It Fl a Ar temporary-directory
Specify an alternative location for the real mount points.
in seconds, that a looked up name remains
cached when not in use. The default is 5 minutes.
Specify the local domain name. If this option is not
given the domain name is determined from the hostname.
Specifies the kernel architecture. This is used solely
to set the ${karch} selector.
Specify a logfile in which to record mount and unmount events.
the log messages will be sent to the system log daemon by
The name referred to by ${rhost} is normalized relative to the
host database before being used. The effect is to translate
aliases into ``official'' names.
Outputs the process-id of
to standard output where it can be saved into a file.
will scan the mount file table to determine which filesystems
are currently mounted. Whenever one of these would have
.It Fl t Ar interval.interval
in tenths of a second, between
The default is 0.8 seconds.
The second values alters the retransmit counter.
Useful defaults are supplied if either or both
Version. Displays version and configuration information on standard error.
in seconds, between attempts to dismount
filesystems that have exceeded their cached times.
The default is 2 minutes.
domain from which to fetch the
The default is the system domain name.
This option is ignored if
support is not available.
Specify run-time logging options. The options are a comma separated
list chosen from: fatal, error, user, warn, info, map, stats, all.
Select from a variety of debug options. Prefixing an
reverses the effect of that option. Options are cumulative.
The most useful option is
is only used for debugging other options are not documented here:
the current supported set of options is listed by the
and a fuller description is available in the program source.
directory under which filesystems are dynamically mounted
Some care may be required when creating a mount map.
filesystem can be incredibly inefficient.
In most implementations of
their interpolations are not cached by
the kernel and each time a symbolic link is
A large improvement in real-time
performance could be gained by adding a cache somewhere.
with a suitable incarnation of the auto-mounter
results in a large real-time speedup, but also causes a large
number of process context switches.
A weird imagination is most useful to gain full advantage of all
.%T Amd \- The 4.4 BSD Automounter
<jsp@doc.ic.ac.uk>, Department of Computing, Imperial College, London, UK.
utility first appeared in 4.4BSD.