Nix: Echo and sudo for files owned by root

If you’re not root, and you want to modify a file owned by root (say /root/tarsnap-backup.sh), this won’t work:

sudo echo '#!/bin/sh
/usr/bin/tarsnap -c \
  -f "$(uname -n)-$(date +%Y-%m-%d_%H-%M-%S)" \
  /home/simon/team-storage' > /root/tarsnap-backup.sh

But this will:

echo '#!/bin/sh
/usr/bin/tarsnap -c \
  -f "$(uname -n)-$(date +%Y-%m-%d_%H-%M-%S)" \
  /home/simon/team-storage' | sudo tee /root/tarsnap-backup.sh > /dev/null

Via @simonw.