/sbin/telinit is linked to /sbin/init. It takes a one-character argument and signals init to perform the appropriate action.
Init listens on a fifo in /run, /run/initctl, for messages. Telinit uses this to communicate with init.
Does the first sentence mean that
telinit is a symlink to
init? If yes, is it correct that
init are run in the same process (e.g. maybe by some file lock) ? If yes, how can
telinit communicate with
init using FIFO or signals?
For comparison, in Systemd,
systemctl are different program files. Does
telinit perform the same role to
init in sysvinit, as