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 APIs to introspect and enumerate devices on the
15 local system.
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17 All functions require a libudev context to operate. This context can be
18 create via udev_new(3). It is used to track library state and link
19 objects together. No global state is used by libudev, everything is
20 always linked to a udev context.
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22 All functions listed here are thread-agnostic and only a single
23 specific thread may operate on a given object during its entire
24 lifetime. It's safe to allocate multiple independent objects and use
25 each from a specific thread in parallel. However, it's not safe to
26 allocate such an object in one thread, and operate or free it from any
27 other, even if locking is used to ensure these threads don't operate on
28 it at the very same time.
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30 To introspect a local device on a system, a udev device object can be
31 created via udev_device_new_from_syspath(3) and friends. The device
32 object allows one to query current state, read and write attributes and
33 lookup properties of the device in question.
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35 To enumerate local devices on the system, an enumeration object can be
36 created via udev_enumerate_new(3).
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38 To monitor the local system for hotplugged or unplugged devices, a
39 monitor can be created via udev_monitor_new_from_netlink(3).
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41 Whenever libudev returns a list of objects, the udev_list_entry(3) API
42 should be used to iterate, access and modify those lists.
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44 Furthermore, libudev also exports legacy APIs that should not be used
45 by new software (and as such are not documented as part of this
46 manual). This includes the hardware database known as udev_hwdb (please
47 use the new sd-hwdb(3) API instead) and the udev_queue object to query
48 the udev daemon (which should not be used by new software at all).
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51 udev_new(3), udev_device_new_from_syspath(3), udev_enumerate_new(3),
52 udev_monitor_new_from_netlink(3), udev_list_entry(3), systemd(1), sd-
53 device(3), sd-hwdb(3), pkg-config(1)
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57systemd 248 LIBUDEV(3)