I have experienced this problem too. Adding the -e flag, substituting printf for echo, or changing the shebang line into #!/bin/dash fixes the issue, as does switching /bin/sh from Bash to Dash by running dpkg- reconfigure dash. My guess is that this is a Dashism, i.e. an incompatibility with systems configured to use Bash as /bin/sh, as the two shells are not 100% compatible.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1876331 Title: update-grub fails to add ZFS menu entries To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1876331/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs