Z:gnu-www-ja-stallman-kth--095db6-Features that I believe must b/en

Features that I believe must be added include: Version numbers, undeletion, information on when and how and where the file was backed up on tape, atomic superseding of files. I believe that it is good that in Unix when a file is being written, you can already look at what's going there, so for example, you can use &ldquo;tail&rdquo; to see how far the thing got, that's very nice. And if the program dies, having partly written the file, you can see what it produced. These things are all good, but, that partly written output should not ever be taken for the complete output that you expected to have eventually. The previous version of that should continue to be visible and used by everyone who tries to use it, until the new version is completely and correctly made. This means that the new version should be visible in the file system but not under the name it is supposed to have. It should get renamed when it's finished. Which is by the way what happens in ITS, although there each user program has to do this explicitly. For Unix compatibility with the user programs, it has to happen invisibly.