Re: Udev rule $attr substitution

[Josua Dietze <digidietze@draisberghof.de>]

Am 22.12.2010 09:51, schrieb Martin Pitt:
>> But I might add that there is certainly some documentation lacking
>> on this one, practially everything I found was outdated or
>> inaccurate ...
>
> This is indeed a common trap, so some time ago I tried to point this
> out more clearly in the manpage:
>
>        $attr{file}, %s{file}
>             The value of a sysfs attribute found at the device, where all keys
>             of the rule have matched. If the matching device does not have such
>             an attribute, and a previous KERNELS, SUBSYSTEMS, DRIVERS, or ATTRS
>             test selected a parent device, use the attribute from that parent
>             device.
>
> This tries to point out that this won't match attributes from any
> parent device. Do you think this paragraph is unclear? If so, do you
> have a suggestion how to improve it? Or did you not see it in the
> first place?

The entry in the current man page is fine.

I was broadly referring to the documentation floating around in the 
Web, examples, howtos and forum discussions. Nothing of your 
responsibility, really.

What's a bit unfortunate though is the discrepancy between man pages 
and functionality of versions before the man page correction. 
OpenSUSE 11.3 ships with v. 157 which claims to do the upward chain 
search for $attr but doesn't.

Maybe an "official" udev page consisting of the current man page and 
two or three additional notes regarding changes in previously 
available features would help. Or does it exist and I missed it?

Just my 2c,

Josua Dietze