Sometimes I like to switch from a session to another just for practice and improve my configs, but I don’t
like display or login managers, I prefer using startx.
Before I search how to switch from depending on TTYs, the last section of my ~/.xinitrc looked as follows:
session=${1:-bspwm}
case $session in
bspwm ) exec bspwm;;
i3|i3wm ) exec i3;;
# No known session, try to run it as command
* ) exec $1;;
esac
So to run another session than the default I had to type:
startx ~/.xinitrc i3
Now i connect automatically after entering my username and password according to the TTY with this code instead: tty1=bspwm tty2=i3 tty3=some other WM/DE
# refers to ~/.zlogin
case $(tty | cut -b9-) in
(1) exec bspwm;;
(2) exec i3;;
(3) some other WM/DE;;
esac
To do so I’ve created a ~/.zlogin and made it executable chmod +x ~/.zlogin (zsh users)
#!/bin/sh
#~/.zlogin
# Auto startx depending on the tty
if [[ -z $DISPLAY ]] && (( $EUID != 0 )) {
[[ ${TTY/tty} != $TTY ]] && (( ${TTY:8:1} <= 3 )) &&
startx 1>~/.xsession-errors 2>&1 &
}
Give it a try 
