Description: Clarify that when called with a time shutdown will not exit.
 That's important to know for programs or scripts that call shutdown … time
 because they will never proceed after having called it (unless they fork,
 exec or similar of course).
 Point in case: unattended-upgrades gets caught by this.
Author: Tomas Pospisek <tpo@debian.org>

--- a/man/shutdown.8
+++ b/man/shutdown.8
@@ -132,6 +132,10 @@ When shutdown is called with the -n flag
 .\"{{{  time
 .IP \fItime\fP
 When to shutdown.
+If a
+\fItime\fP
+is given then the
+\fBshutdown\fP command will not exit but instead count down until reboot.
 .\"}}}
 .\"{{{  warning-message
 .IP "\fIwarning message\fP"