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33 .Nd "device state change daemon"
40 daemon provides a way to have userland programs run when certain
43 The following options are accepted.
44 .Bl -tag -width indent
46 Enable debugging messages.
48 Run in the foreground instead of becoming a daemon.
50 Do not process all pending events before becoming a daemon.
51 Instead, call daemon right away.
53 .Sh IMPLEMENTATION NOTES
57 is a system daemon that runs in the background all the time.
58 Whenever a device is added to or removed from the device tree,
60 will execute actions specified in
66 when an Ethernet adapter is added to the system, and kill the
68 instance when the same adapter is removed.
69 Another example would be for
71 to use a table to locate and load via
73 the proper driver for an unrecognized device that is added to the system.
81 This device driver has hooks into the device configuration system.
82 When nodes are added or deleted from the tree, this device will
83 deliver information about the event to
87 has parsed the message, it will search its action list for that kind
88 of event and perform the action with the highest matching value.
89 For most mundane uses, the default handlers are adequate.
90 However, for more advanced users, the power is present to tweak every
91 aspect of what happens.
98 and uses that file to drive the rest of the process.
99 While the format of this file is described in
101 some basics are covered here.
104 section, one can define multiple directories to search
106 All files in these directories whose names match the pattern
109 These files are intended to be installed by third party vendors that
110 wish to hook into the
112 system without modifying the user's other
117 receives are forwarded to the
120 .Pa /var/run/devd.pipe .