chroot() changes the root directory to that specified in
path. This directory will be used for pathnames beginning with /. The root
directory is inherited by all children of the current process.
Only a privileged process (Linux: one with the
CAP_SYS_CHROOT capability) may call
chroot(2).
This call changes an ingredient in the pathname resolution process
and does nothing else.
This call does not change the current working directory,
so that after the call ‘.’ can be outside the tree rooted at ‘/’.
In particular, the superuser can escape from a ‘chroot jail’
by doing ‘mkdir foo; chroot foo; cd ..’.
This call does not close open file descriptors, and such file
descriptors may allow access to files outside the chroot tree.
