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33 .Nd "device state change daemon"
42 daemon provides a way to have userland programs run when certain
45 The following options are accepted.
46 .Bl -tag -width ".Fl f Ar file"
48 Run in the foreground instead of becoming a daemon and log additional information for debugging.
50 Use configuration file
52 instead of the default
56 is specified more than once, the last file specified is used.
58 Limit concurrent socket connections to
60 The default connection limit is 10.
62 Do not process all pending events before becoming a daemon.
63 Instead, call daemon right away.
66 Only log messages at priority LOG_WARNING or above.
68 .Sh IMPLEMENTATION NOTES
72 is a system daemon that runs in the background all the time.
73 Whenever a device is added to or removed from the device tree,
75 will execute actions specified in
81 when an Ethernet adapter is added to the system, and kill the
83 instance when the same adapter is removed.
84 Another example would be for
86 to use a table to locate and load via
88 the proper driver for an unrecognized device that is added to the system.
96 This device driver has hooks into the device configuration system.
97 When nodes are added or deleted from the tree, this device will
98 deliver information about the event to
102 has parsed the message, it will search its action list for that kind
103 of event and perform the action with the highest matching value.
104 For most mundane uses, the default handlers are adequate.
105 However, for more advanced users, the power is present to tweak every
106 aspect of what happens.
113 or the alternate configuration file specified with a
115 option and uses that file to drive the rest of the process.
116 While the format of this file is described in
118 some basics are covered here.
121 section, one can define multiple directories to search
123 All files in these directories whose names match the pattern
126 These files are intended to be installed by third party vendors that
127 wish to hook into the
129 system without modifying the user's other
134 allows only one active reader,
136 multiplexes it, forwarding all events to any number of connected clients.
137 Clients connect by opening the SOCK_SEQPACKET
140 .Pa /var/run/devd.seqpacket.pipe .
142 .Bl -tag -width ".Pa /var/run/devd.seqpacket.pipe" -compact
143 .It Pa /etc/devd.conf
147 .It Pa /var/run/devd.seqpacket.pipe
150 to communicate with its clients.
151 .It Pa /var/run/devd.pipe
152 A deprecated socket retained for use with old clients.
160 utility first appeared in