Re: How to document dimension units for virtual files?

[Pavel Machek <pavel@ucw.cz>]

Hi!

> > > 2. Encode dimension unit into filename (e.g. onlinetime_ms or
> memory_kb)
> >
> > This is the recommended one.
> > - simple to implement and understand on both sides
> >
> > - if you change units, you notice breaking userspace immediately
> >   and can even notice it being used in closed source tools
> >   with a simple strace
> >
> > - no parsing involved, as the author of the user space tool
> >   usually assumes the unit implicitly (like "programming by contract",
> where
> >   the "contract" is the filename, which is quite easy to check for.
> >
> > - you can keep a legacy interface with neglible effort and code wastage
> >
> > - many advantages I forgot :-)
> >
> 
> I also think that this is the best solution. It would be nice to have
> that documented somewhere. Maybe in the Documentation directory
> something like:
> 
> Howto export data in virtual files
> ==================================
> 
> If you want to export data to userspace via virtual filesystems
> like procfs, sysfs, debugfs etc., the following rules are recommended:

...yes please... such patch would be nice.

> - Export only one value in one virtual file.
> - Data format should be as simple as possible.
> - Use ASCII formated strings, no binary data if possible.
> - If data has dimension units, encode that in the filename.
>   Please use the following suffixes:
>   * kb: Kilobytes
>   * mb: Megabytes

just use B for bytes....

-- 
Thanks for all the (sleeping) penguins.