[gdm-list] Session identification and postlogin

[Francesco Fumanti <francesco fumanti gmx net>]

Hello,




I am trying to do a configuration to be able to start and quit an 
simple onscreen keyboard (not gok; another one called onboard to be 
precise) during gdmlogin. (I will also start another utility, but 
that is not relevant here.)

A dwell gesture will not start onboard directly; it will start a 
script that starts and quits onboard. To check whether onboard is 
already running, the script creates a pidfile with the pid of the 
started onboard instance; if onboard is already running, the script 
gets the pid from the pidfile, kills onboard and removes the pidfile. 
This is working properly on my single user setup.




In order to make it also work with simultaneous multiple user, I 
added the value of $DISPLAY to the name of the pidfile:

pidfile="/tmp/onboard-at-gdmlogin-display-${DISPLAY}.pid"

Now I wonder whether this will also work in the case of users with 
multiple screens. Can anybody please confirm it?




Moreover, when gdmlogin quits, the pidfile will remain present on the 
system if the user did not quit onboard. So I will create a "cleanup" 
script to remove the pidfile, and call it from PostLogin.

Could anybody please confirm that it is the correct way to do it?

Moreover, could anybody please confirm that during PostLogin, the 
variable $DISPLAY will still have the same value that it had during 
the gdmlogin session? Otherwise, the cleanup script will not be able 
to reconstruct the name of the pidfile.

If $DISPLAY has changed, could anybody please tell me how I should proceed?


Thanks in advance.

Francesco


PS: Once I have it all running, I will put everything online and send 
a link to it to this mailing list.