at: add page

pages/linux/at.md

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+# at
+
+> Executes commands at a specified time.
+
+- Open an `at` prompt to create a new set of scheduled commands, press Ctrl+D to save and exit:
+
+`at {{hh:mm:ss}}`
+
+- Execute the commands and email the result using a local mailing program such as sendmail:
+
+`at {{hh:mm:ss}} -m`
+
+- Execute a script at the given time:
+
+`at {{hh:mm:ss}} -f {{path/to/file}}`