Errors in .xsession-errors, which ones matter?

[Chris Green]

When I start up xfce4 I get the following in .xsession-errors, which
ones do I need to worry about?

    /usr/X11R6/lib/X11/xdm/Xsession: line 36: xmodmap: command not found
    stderr is not a tty - where are you?
    which: no xfce4-session in
    (/home/chris/bin:/home/chris/bin:/usr/local/bin:/usr/
    bin:/bin:/usr/X11R6/bin:/usr/games:/opt/www/htdig/bin:/usr/lib/java/bin:/usr/lib
    /java/jre/bin:/usr/share/texmf/bin:.)
    Xlib:  extension "RENDER" missing on display "chris.isbd.co.uk:0.0".
    ** Message: Cannot connect to session manager
    ** Message: xfdesktop: running without session manager
    ** Message: xfce4-panel: Running without session manager
    ** Message: xfce4-panel: module eyes successfully loaded
    ** Message: xfce4-panel: module systembuttons successfully loaded
    ** Message: xfce4-panel: module tl successfully loaded
    ** Message: xfce4-panel: module switcher successfully loaded
    ** Message: xfce4-panel: module mixer successfully loaded
    ** Message: xfce4-panel: module clock successfully loaded
    ** Message: xfce4-panel: module separator successfully loaded
    ** Message: xfce4-panel: module systray successfully loaded
    ** Message: xfce4-panel: module mailcheck successfully loaded
    ** Message: xfce4-panel: module pager successfully loaded
    Xlib:  extension "RENDER" missing on display "chris.isbd.co.uk:0.0".
    Xlib:  extension "RENDER" missing on display "chris.isbd.co.uk:0.0".


I don't think xmodmap is trying to do anything important so that
probably doesn't matter.

What's that bit about "stderr is not a tty - where are you?", rather
odd.

It's the "no xfce4-session" bit that worries me most.  There isn't an
executable called xfce4-session anywhere on my system, should there
be?

The missing "RENDER" must just be a limitation of my X server.

-- 
Chris Green (chris at areti.co.uk)