Sometimes you may want to start a couple of programs just after an interactive login to your favourite shell, which in my case would be zsh.
For example – I use Emacs as daemon process(emacs —daemon). I cannot use an init script to start it since the daemon is usable on a per user basis. The solution in this case is really simple – just create a .zlogin file in your home folder and put in it all the commands you want executed after you’ve logged into the shell. In my case I put:
there and as soon as I’m logged in, the Emacs daemon is up waiting for incoming connections.