uptime: Add -s/--since option to output only when the system came online

This also matches Linux and the BSDs.
Author: https://github.com/AtkinsSJ Commit: 7bcb560060 Pull-request: https://github.com/SerenityOS/serenity/pull/22917 Reviewed-by: https://github.com/tcl3 ✅
2025-09-24 18:28:57 +00:00 · 2024-01-24 12:46:13 +00:00 · 2024-01-24 12:46:13 +00:00 · 7bcb560060 · 2024-07-17 07:43:44 +09:00
commit 7bcb560060
parent 8faeb13036
2 changed files with 13 additions and 1 deletions
--- a/Base/usr/share/man/man1/uptime.md
+++ b/Base/usr/share/man/man1/uptime.md
@ -16,6 +16,7 @@ This information includes when the system came online and how long it has been u
 ## Options

 * `-p`, `--pretty`: Output only the uptime, in human-readable format.
+* `-s`, `--since`: Output only the datetime when the system came online.

 ## Examples

@ -28,3 +29,8 @@ $ uptime
 $ uptime -p
 Up 2 minutes, 20 seconds
 ```
+
+```sh
+$ uptime -s
+2024-01-24 06:23:27
+```