what does shutdown -p command do?

Question

In Linux, what does shutdown -p command do, will it directly power off the system without Halting? if it halts the system first then power off, then can we directly power off without halting using any command?

Answer 1

shutdown -P sends an ACPI signal telling the computer to completely power off. However, the shutdown command by default powers off the machine, so unless you for some reason need to specify to power off, the normal shutdown command will do it.

You don't need to use any halt commands before using shutdown to power off, either, shutdown -P will completely power off the system without any need to run any halting commands.