Thanks for your answer!
ed2345 wrote:
In recent releases, there has been an improvement in the Undo command. So if you realize right away that you did something wrong, you can (immediately, before you do anything else) go to Edit > Undo. This would work in the case you describe.
Yes I know that. But if you don't notice you've changed something unintentionally, you won't use Undo. And when iTunes is closed, and you notice such a modification later, it's too late.
Setting the whole folder to Read Only will require that you have to unset it before you do anything, and the reset it when you are done, which will be a bother and is easy to forget to do.
But can you confirm that it's possible to just playback music in a Read-Only iTunes library folder without problems? (I add new music only once a week.)
Also, make sure that you back up your library on a regular basis.
I do this every night, but the last unintended modification I noticed had been done about 6 months ago, and I didn't keep such old backups. :-(