Documentation request: List of sys and other such files

Carsten Haitzler (The Rasterman) raster at
Sat May 31 04:25:03 CEST 2008

On Sat, 31 May 2008 03:37:02 +0200 Joerg Reisenweber <joerg at>

> Am Sa  31. Mai 2008 schrieb Andy Green:
> > Somebody in the thread at some point said:
> > | Extension question: How about a list of all such files and devices,
> > | along with a short description of their behavior?
> > |
> > | Michael
> > |
> > | Joerg Reisenweber wrote:
> > |> related question: where's the watchdog-timer device I regularly write
> > |> some "garbage" to it to keep NEO from suspending? Scriptable solution
> > |> preferred!
> > 
> > Yeah.  How about those things.
> > 
> > -Andy
> > 
> hey don*t take this easy! It's hard to find any info on it, and not even an 
> experienced developer has spare time to "reverse-engineer" the driver code to 
> get it. There HAS TO BE a man page. If there is already: probably my fault, 
> toss me a pointer.

in userspace its simple like this:

1. screenblank kickis in (if enabled).
2. a timer starts for N seconds (default is 10)
2.1. if screenblank interrupted (but touschreen press) timer is aborted
3. when timer ticks off "apm -s" is executed.

the rest is the job of the apm subsystem and anything intercepting apm suspend
requests via the apm bios. technically qpe should be doing this and halting any
suspend requests during a phone call for example. no reason any other process
can't do the same. apparently the suspend can't be stopped - but it can be
indefinitely delayed (which is kind of odd - and well... bad - but that's the
infra used).

Carsten Haitzler (The Rasterman) <raster at>

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