Filesystem read offsets

bjornbytes / lovr

Lua Virtual Reality Framework

https://lovr.org

MIT License

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Filesystem read offsets #581

Closed bjornbytes closed 1 year ago

bjornbytes commented 2 years ago

It's important to be able to read a range of bytes from a file. There are 2 ways this could be accomplished:

Add an offset parameter to lovr.filesystem.read. This could also get added to .write.
Add File objects like LÖVE, which would support seeking and reduce overhead of consecutive random reads from the same file.
- There is already an incomplete implementation of File objects (used in forks), but it isn't exposed to Lua yet.

bjornbytes commented 2 years ago

I've also been thinking about adding Archive objects, for reading (and potentially writing) of archives like zip/tar. It's interesting to think about how File objects (and seeking) interacts with archives.

bjornbytes commented 2 years ago

Other considerations after thinking about it more:

Are pread/pwrite portable enough for us? Also the windows support with IO completion ports or w/e.
It's possible to do this today with string.sub. Is the offset param worth it compared to the existing solution?

bjornbytes commented 1 year ago

Args on .read/.write get too messy/inconsistent. I think this should be implemented as File objects. This isn't immediately planned though.

bjornbytes commented 1 year ago

File object was added in #721