b20a0e49c8
The new systemd in 19.09 gives an "Access Denied" error when doing "systemctl daemon-reexec" on an 19.03 system. The fix is to use the previous systemctl to signal the daemon to re-exec itself. This ensures that users don't have to reboot when upgrading from NixOS 19.03 to 19.09.
*** NixOS *** NixOS is a Linux distribution based on the purely functional package management system Nix. More information can be found at http://nixos.org/nixos and in the manual in doc/manual.