[Debian-eeepc-devel] [eeepc-acpi-scripts PATCH] Allow X detection without an existing console/terminal session

[Darren Salt]

I demand that Damyan Ivanov may or may not have written...

> -=| Darren Salt, Fri, Oct 24, 2008 at 12:35:43PM +0100 |=-
>> I find that either the first method in detect_x_display() for finding a
>> logged-in user succeeds or the second method also fails. This patch
>> replaces the second method: rather than extract all logged-in users, look
>> for a process which is using a console and has certain environment
>> variables which then are used for OSD purposes. (The OSD will also work
>> if a login manager is currently in control.)

I forgot to mention that I find that the first method only succeeds if a user
is currently logged in via a console or X terminal.

> -        _user=$( who | head -n 1 | cut -d' ' -f1 )
> +        #_user=$( who | head -n 1 | cut -d' ' -f1 )
> +        _user=$(ps -o pid= -t tty$(fgconsole) | sed -e 's/^\s\+//g' | cut
-d' ' -f1)
> +        if [ "${_user}" != '' ]; then
> +            eval $(sed -e 's/\x00/\n/g' /proc/${_user}/environ | grep
'^\(DISPLAY\|XAUTHORITY\)=' | sed -e "s/'/'\\\\''/g; s/=/='/; s/$/'/")
> +            DISPLAY="${DISPLAY:-:0}"
> +            export XAUTHORITY
> +            export DISPLAY
> +            user=root
> +            home=$(getent passwd $_user | cut -d: -f6)
> +        fi
> +        return

> Looks good and the possibility to have OSD notifications before logging in
> would be very nice.

I'm not certain that the first detection method is actually still needed with
this patch; I've not (yet) tested.

> Shouldn't "user=root" actually be "user = $_user"? For example if X was
> started with "startx" from the console...

That doesn't seem to matter, and I don't really see how we could reliably set
it anyway; $_user contains an X process ID, so we'd need to find another
process which shares the same credentials ($DISPLAY and $XAUTHORITY) – but
there's no guarantee that that's owned by whoever actually logged in. (That
said, it's likely to be that user or root.)

-- 
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