OSX infinite login issue

OSX is a Linux cousin, if you know about the command line, you can fix problems, your system shouldn't be a black box.  So when your login on OSX hangs, please check your network connection, and if it takes too long, maybe you have a problem in your filesystem or an infinite loop on osx login.

Even if you try to log in with varios accounts, you will not be stuck.

The following procedure is offered with NO warranties, so you are on your own, please do not complain to me if it does not work.

Shut down the computer, and as soon as it's booting press 
Cmd s, it will bring you to a CLI where you are instructed to fsck your system and remount it in readwrite mode, not bad to do that. Then you'll be able to type the following code to clean your startup session:

find /private/var/folders/com.apple.LaunchServices-*.csstore -name "" -exec rm '{}' ';'
exit

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