Ok, I tired
1. "debug" cheatcode , no help,
2. try to catch what has written in boot screen : I saw that : ERRORS are
cannot open display "default display"
and
can't open display
3. sorry but "read" command does not work, it didn't stop to read anything.
4. I add a command "setxkbmap tr" at the end of "/etc/rc.d/rc.local" file which should be another way to do the trick, but it didn't work.
In summary :
I only see the errors "cannot open default display" ... the only tip.
I could not start a simple Xkeyboard layout change code in Porteus. I am very sad...

I can do it manually (i.e. running a simple script file after system started) but if I can do it automatically, why do i put an extra effort?