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libudev(3)


NAME

   libudev - API for enumerating and introspecting local devices

SYNOPSIS

   #include <libudev.h>

   pkg-config --cflags --libs libudev

DESCRIPTION

   libudev.h provides APIs to introspect and enumerate devices on the
   local system.

   All functions require a libudev context to operate. This context can be
   create via udev_new(3). It is used to track library state and link
   objects together. No global state is used by libudev, everything is
   always linked to a udev context. Furthermore, multiple different udev
   contexts can be used in parallel by multiple threads. However, a single
   context must not be accessed by multiple threads in parallel. The
   caller is responsible for providing suitable locking if they intend to
   use it from multiple threads.

   To introspect a local device on a system, a udev device object can be
   created via udev_device_new_from_syspath(3) and friends. The device
   object allows one to query current state, read and write attributes and
   lookup properties of the device in question.

   To enumerate local devices on the system, an enumeration object can be
   created via udev_enumerate_new(3).

   To monitor the local system for hotplugged or unplugged devices, a
   monitor can be created via udev_monitor_new_from_netlink(3).

   Whenever libudev returns a list of objects, the udev_list_entry(3) API
   should be used to iterate, access and modify those lists.

   Furthermore, libudev also exports legacy APIs that should not be used
   by new software (and as such are not documented as part of this
   manual). This includes the hardware database known as udev_hwdb (please
   use the new sd-hwdb(3) API instead) and the udev_queue object to query
   the udev daemon (which should not be used by new software at all).

SEE ALSO

   udev_new(3), udev_device_new_from_syspath(3), udev_enumerate_new(3),
   udev_monitor_new_from_netlink(3), udev_list_entry(3), systemd(1), sd-
   device(3), sd-hwdb(3), pkg-config(1)



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