Configuration files for i3 window manager, Emacs, nano, bash, urxvt and other environment.

Generally, there are two ways launching X – using a display manager (DM) or startx. DM takes care about sessions, switching display between users, consolekit session and some other stuff.

1. login via tty2;
2. ~/.bashrc checks for DISPLAY variable and current tty, and, if DISPLAY is not set and tty is /dev/tty2, it launches startx and passes options to X;
3. startx is actually a wrapper over xinit which in its turn launches X with passed options (the difference between startx and xinit is AFAIR, startx creates file with auth information for the X server automatically, so one shouldn’t worry about it);
4. After X is up, xinit launches ~/.xinitrc file, and all the commands from there. Window manager (WM) is also intended to run from there.

This is how pstree looks that way

1. In the runlevel "default" (its number usually between 3 and 5) starts a DM script which do authentication job, runs X (via startx, xinit or directly) and,after successful login, launches a session which passes you to the graphical environment. If you choose option "custom session" which is present in every normal DM, instead of any "default" or "prepared" session, your ~/.xsession file will be launched. This file is also handy to customize if you aren’t going to refuse of a DM usage yet;
2. ~/.xsession may launch your WM or whatever in same manneer as ~/.xinitrc does.

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URxvt may use resources from ~/.Xdefaults or via certain X RESOURCE_MANAGER, managed by xrdb utility, which can load user’s ~/.Xresources file to update resource base (look also at ~/.xinitrc where xrdb is calling). By default it will look for ~/.Xdefaults then in resources of the root window. The difference between these files is

~/.Xdefaults

• is obsolete;
• AFAIR, is just a file and nothing more;
• and does not support non-local X clients.

~/.Xresources

• is a modern way to set resources on a WM_CLASS basis;
• is also used for setting per-user X display options, like dpi.

when bash starts, it tries to source /etc/profile, then ~/.bash_profile, ~/.bash_login or ~/.profile, usually ~/.bash_profile is present and ~/.bashrc is sourced from there. To customize keybindings ~/.inputrc is used (See also /etc/inputrc). With these files, and also using urxvtd and urxvtc one can get terminal as light as a feather and have same keybindings as in preffered editor.