[jefftk]

Doesn't this mean that most programs you might want to use with the FUSE API won't actually work? They'll do fine for a while, until they try to seek, and then they'll get an error?

Or is there a large group of programs that only ever write sequentially?

[jsnell]

I'd think non-appending writes are quite rare in practice, other than databases. Even when the application is logically overwriting data, in other kinds of programs it's almost always implemented as writing to a new file + an atomic rename, not in-place modification.

[dontlaugh]

Even databases tend to do sequential writes, whether to a WAL or LSM tree.

[hawski]

Most programs either write a full file every time and replace the old file by a single move or append to an old file. Writting in the middle could happen in a program writting to some kind of archive or disk image. There is probably a whole group of programs that do this I'm not familiar with, but I'm pretty sure of my first sentence.

[jefftk]

I'm not completely confident (I tried looking in the source and it wasn't immediately obvious) but I think emacs does small in-place edits when you're working with very large files.

[formerly_proven]

sqlite, dbm and similars, various zip libraries and the file formats build on that

[throwawaaarrgh]

well yeah, but there's a lot of things FUSE makes easier. no need to implement a client library, no need to write some custom wrapper or rsync thing to sync files to the bucket or bucket to local system, etc. it won't work for every app but for the ones it does support it saves a ton of extra work and maintenance.