hc
2023-12-11 d2ccde1c8e90d38cee87a1b0309ad2827f3fd30d
kernel/Documentation/ABI/testing/sysfs-uevent
....@@ -6,42 +6,46 @@
66 Enable passing additional variables for synthetic uevents that
77 are generated by writing /sys/.../uevent file.
88
9
- Recognized extended format is ACTION [UUID [KEY=VALUE ...].
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+ Recognized extended format is::
1010
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- The ACTION is compulsory - it is the name of the uevent action
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- ("add", "change", "remove"). There is no change compared to
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- previous functionality here. The rest of the extended format
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- is optional.
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+ ACTION [UUID [KEY=VALUE ...]
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+
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+ The ACTION is compulsory - it is the name of the uevent
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+ action (``add``, ``change``, ``remove``). There is no change
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+ compared to previous functionality here. The rest of the
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+ extended format is optional.
1517
1618 You need to pass UUID first before any KEY=VALUE pairs.
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- The UUID must be in "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
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+ The UUID must be in ``xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx``
1820 format where 'x' is a hex digit. The UUID is considered to be
1921 a transaction identifier so it's possible to use the same UUID
2022 value for one or more synthetic uevents in which case we
2123 logically group these uevents together for any userspace
2224 listeners. The UUID value appears in uevent as
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- "SYNTH_UUID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" environment
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+ ``SYNTH_UUID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx`` environment
2426 variable.
2527
2628 If UUID is not passed in, the generated synthetic uevent gains
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- "SYNTH_UUID=0" environment variable automatically.
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+ ``SYNTH_UUID=0`` environment variable automatically.
2830
2931 The KEY=VALUE pairs can contain alphanumeric characters only.
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+
3033 It's possible to define zero or more pairs - each pair is then
3134 delimited by a space character ' '. Each pair appears in
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- synthetic uevent as "SYNTH_ARG_KEY=VALUE". That means the KEY
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- name gains "SYNTH_ARG_" prefix to avoid possible collisions
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+ synthetic uevent as ``SYNTH_ARG_KEY=VALUE``. That means the KEY
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+ name gains ``SYNTH_ARG_`` prefix to avoid possible collisions
3437 with existing variables.
3538
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- Example of valid sequence written to the uevent file:
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+ Example of valid sequence written to the uevent file::
3740
3841 add fe4d7c9d-b8c6-4a70-9ef1-3d8a58d18eed A=1 B=abc
3942
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- This generates synthetic uevent including these variables:
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+ This generates synthetic uevent including these variables::
4144
4245 ACTION=add
4346 SYNTH_ARG_A=1
4447 SYNTH_ARG_B=abc
4548 SYNTH_UUID=fe4d7c9d-b8c6-4a70-9ef1-3d8a58d18eed
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+
4650 Users:
4751 udev, userspace tools generating synthetic uevents