Update cheatsheets

tldr/linux/systemctl-halt

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+---
+syntax: markdown
+tags: [tldr, linux]
+source: https://github.com/tldr-pages/tldr.git
+---
+# systemctl-halt
+
+> Shut down and halt the system (stop the OS kernel but keep hardware powered on).
+> See also: `halt`.
+> More information: <https://www.freedesktop.org/software/systemd/man/systemctl.html#halt>.
+
+- Halt the system:
+
+`systemctl halt`
+
+- Halt the system immediately without asking services to stop gracefully:
+
+`systemctl halt --force`
+
+- Halt the system immediately without sending notifications to logged-in users:
+
+`systemctl halt --force --no-wall`
+
+- Halt the system immediately without terminating any processes or unmounting filesystems (dangerous, may cause data loss):
+
+`systemctl halt --force --force`
+
+- Schedule a halt at a specific time (e.g., 23:00):
+
+`systemctl halt --when 23:00`
+
+- Schedule a halt after a certain duration (e.g., 2 hours):
+
+`systemctl halt --when +2h`
+
+- Cancel a scheduled halt:
+
+`systemctl halt --when cancel`