Setting environment variable used in a startup script

They're not. Those scripts are not usually sourced during your startup sequence for X, and the shells you start in X are not normally login shells, so they wouldn't runetc-profile.

You're wrong ...

No, no. You do not understand. One has to sourceetc-profile in the startup script initiated by your login or display manager. If it is a xdm-derived login manager, that usually involves sourcing it in GiveConsole, or similar.

Look atetc-X11-Xstartup, for example:

if -xetc-X11-xdm-GiveConsole ; then # we can afford to do this in a subprocess, not that it matters etc-X11-xdm-GiveConsole fi

This is configured in xdm-config:

DisplayManager*startup:usr-X11R6-lib-X11-xdm-Xstartup

Then the variable is available to everything started by the display manager that xdm fires up. Including your shells, and your icons.

It's an admin decision, but the decision can also be made by the user, by sourcing the appropriate files in his .xinitrc, .xclients, .Xclient or whatever his X init sequence runs.

If the variable is not defined in the X init sequence, then it will not be available to the window manager, application launcher, and so on.

So no, he doe NOT need it in the startup script which launches xdm, but in the startup script launched BY xdm. Yu don't seem to grok that.

Peter