1LIBUDEV(3) libudev LIBUDEV(3)
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6 libudev - API for enumerating and introspecting local devices
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9 #include <libudev.h>
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11 pkg-config --cflags --libs libudev
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14 libudev.h provides an API to introspect and enumerate devices on the
15 local system. This library is supported, but should not be used in new
16 projects. Please see sd-device(3) for an equivalent replacement with a
17 more modern API.
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19 All functions require a libudev context to operate. This context can be
20 create via udev_new(3). It is used to track library state and link
21 objects together. No global state is used by libudev, everything is
22 always linked to a udev context.
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24 All functions listed here are thread-agnostic and only a single
25 specific thread may operate on a given object during its entire
26 lifetime. It's safe to allocate multiple independent objects and use
27 each from a specific thread in parallel. However, it's not safe to
28 allocate such an object in one thread, and operate or free it from any
29 other, even if locking is used to ensure these threads don't operate on
30 it at the very same time.
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32 To introspect a local device on a system, a udev device object can be
33 created via udev_device_new_from_syspath(3) and friends. The device
34 object allows one to query current state, read and write attributes and
35 lookup properties of the device in question.
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37 To enumerate local devices on the system, an enumeration object can be
38 created via udev_enumerate_new(3).
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40 To monitor the local system for hotplugged or unplugged devices, a
41 monitor can be created via udev_monitor_new_from_netlink(3).
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43 Whenever libudev returns a list of objects, the udev_list_entry(3) API
44 should be used to iterate, access and modify those lists.
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46 Furthermore, libudev also exports legacy APIs that should not be used
47 by new software (and as such are not documented as part of this
48 manual). This includes the hardware database known as udev_hwdb (please
49 use the new sd-hwdb(3) API instead) and the udev_queue object to query
50 the udev daemon (which should not be used by new software at all).
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53 udev_new(3), udev_device_new_from_syspath(3), udev_enumerate_new(3),
54 udev_monitor_new_from_netlink(3), udev_list_entry(3), systemd(1), sd-
55 device(3), sd-hwdb(3), pkg-config(1)
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59systemd 251 LIBUDEV(3)