FYI this was a fairly straight forward theft of the code from update-initramfs to do the same and I tested by removing several old kernels and seeing that it only ran update-grub once, then installing ( and reinstalling ) a new kernel and seeing that it still ran once. Also manual invocation of update-grub still works.
FYI this was a fairly straight forward theft of the code from update-initramfs to do the same and I tested by removing several old kernels and seeing that it only ran update-grub once, then installing ( and reinstalling ) a new kernel and seeing that it still ran once. Also manual invocation of update-grub still works.