The manual page and help for the jk_init Linux command. It is not an easy task to set up a chroot jail functionally. If, for example, we want the user to be able to run some commands, it is often not enough to simply copy the binary files of the commands into the jail, because many commands require different function libraries, and in many cases also devices under /dev. Finally, you need a shell that starts the commands, etc. These tasks can be automated using the jk_init command.