Slightly simpler is to use Proc::Daemon.

use Proc::Daemon;
Proc::Daemon::Init;
exec @ARGV;
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Or ...

perl -MProc::Daemon -e 'Proc::Daemon::Init; exec @ARGV' some command h
+ere
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The difference is that this will start a new session, making it pretty much impossible that the background process will gain access to any terminal.

I'm sure someone could golf this down further, but I'm just trying to get simpler, not smaller. :-)