Re: [gentoo-user] Is starting xdm enough to see something in X?

[Mark Knecht]

On Fri, May 22, 2009 at 12:54 PM, Alan McKinnon <alan.mckinnon@×××××.com> wrote:
> On Friday 22 May 2009 21:19:40 Mark Knecht wrote:
>> On Fri, May 22, 2009 at 12:08 PM, Matt Harrison
>>
>> <iwasinnamuknow@×××××××××.com> wrote:
>> > Mark Knecht wrote:
>> >> On Fri, May 22, 2009 at 11:49 AM, bn <brullonulla@×××××.com> wrote:
>> >>> Mark Knecht ha scritto:
>> >>>> Title sort of says it. I have an old machine that I'm setting up as a
>> >>>> Myth server. I didn't want X on the machine but I'm having trouble so
>> >>>> I emerged xdm and start it using /etc/init.d/xdm start. The  drivers
>> >>>> get loaded but I get a black screen. No error message in the X log
>> >>>> file.
>> >>>>
>> >>>> I haven't messed with X at this level before. What's the minimum test
>> >>>> of X that would display a terminal or something very basic?
>> >>>
>> >>> Have you tried
>> >>>
>> >>> startx /usr/bin/xterm
>> >>
>> >> Yes. Same black screen. Nothing else going on. The processes show up
>> >> in ps aux, X as root, xterm as me.
>> >
>> > I've found before that if everything seems to be running (can list X
>> > processes and logs look fine) but you still don't see anything, it's
>> > possible it is your monitor. I used to use a really old 15" CRT for a
>> > server but it just wouldn't run X at anything over 640x480. Modern
>> > monitors will at least tell you if the resolution/refresh is out of
>> > limits, but older ones don't often. Try with a different monitor if that
>> > one is old or suspect.
>> >
>> > ~Matt
>>
>> Good point. I'll hook the machine up to a very good monitor later today.
>> Thanks.
>
> You need to run an X-server, not the one that is displaying xdm because that
> will only run xdm and once you authenticate will launch an entirely different
> session. Either launch the failsafe session, it gives you twm on gentoo with a
> single xterm, or ditch xdm and run startx.
>
> You can also run xinit (startx is a wrapper script around xinit that launches
> user-defined apps) and that gives you plain X without a window manager so you
> need to put at least xterm into .xinitrc
>
>> One question about this X stuff. Is there any difference at all at the
>> application level if I run an app displaying on the monitor of that
>> machine, or use ssh -X -Y -C and run the app displaying on a remote
>> machine?
>
> No difference whatsoever for basic apps. X is network transparent, meaning
> that the X client reads and writes a Unix socket, TCP socket, or whatever else
> you can dream up. However, I'm sure you will find that recent fancy stuff like
> compiz and OpenGL don't work as expected.
>
>> If there is absolutely no difference then I don't need to bother with
>> this. If there is then I do. The real issue here is that Myth doesn't
>> work. If I can be certain that displaying Myth apps on a remote
>> screen, such as mythtv-setup or mythfrontend, is really the same then
>> I'll just do that. However those apps are currently failing so I'm
>> trying to eliminate issues, and possibly creating one I don't care
>> about in doing that!
>
> Running X apps locally locally tests your X libs and your X server.
> Running X apps remotely tests the X libs
>

Thanks Alan,
   OK, I switched to a known good monitor, left xdm turned off and
used startx at my command line. I see all the right stuff in ps but
still no video, and it seems that I've lost control of my keyboard as
I cannot use Alt-Ctrl-F2 to get to another console. (The machine
currently doesn't have a mouse)

MacMini ~ # ps aux | grep x
<SNIP>
mark      4643  0.0  0.2   3324  1348 tty1     S+   13:24   0:00
/bin/sh /usr/bin/startx
mark      4659  0.0  0.2   3680  1104 tty1     S+   13:24   0:00 xinit
/etc/X11/xinit/xinitrc -- -nolisten tcp -br -auth
/home/mark/.serverauth.4643 -deferglyphs 16
mark      4679  0.0  0.6   8216  3252 tty1     S    13:24   0:00 xterm
-geometry 80x66+0+0 -name login
mark      4694  0.0  0.6   8376  3488 tty1     S    13:24   0:00
xclock -geometry 50x50-1+1
mark      4695  0.0  0.6   8208  3252 tty1     S    13:24   0:00 xterm
-geometry 80x50+494+51
mark      4696  0.0  0.6   8196  3236 tty1     S    13:24   0:00 xterm
-geometry 80x20+494-0
root      4735  0.0  0.1   2840  1020 pts/3    R+   13:26   0:00 ps aux
root      4736  0.0  0.1   2060   580 pts/3    R+   13:26   0:00 grep
--colour=auto x
MacMini ~ #

If I use top in a terminal and kill startx and xinit then I get back
to my login console.

Possibly xorg-server-1.5 isn't compatible with a 2.6.24 kernel?

Maybe I should move this to the Power PC group. Likely I'll find
someone there with direct experience. Still, I appreciate the wider
audience of gentoo-user.

- Mark