Can Ed be configured to automatically create backup files?

Question

Is there a way to have Ed create backups of the file currently loaded into the buffer. On occasion I have inadvertently overwritten my file and found it's not recoverable. I.e. making a backup file with a tilde appended to the original file name (e.g., myfile.txt~), which would contain the previous version of the file.

Answer 1

The ed editor does not provide a backup facility (or any way to configure it, at all). Writing the editing buffer back to disk with the w command overwrites the original file.

It is up to you to edit a copy of your original data or save the text with a new filename, either by saving using w some-filename or using f some-filename followed by w.

Some modern filesystems provide snapshotting facilities that would let you retrieve the overwritten data, or you could fetch it from a recent backup, if you overwrote it in error.