Error reading files using tinygo

[adamreese]

When trying to read a file in tinygo it returns the error open /test.txt: errno 76

Here is my test application https://github.com/adamreese/spin-fs-issue

[itowlson]

That seems to be a capabilities error:

https://github.com/bytecodealliance/wasi/blob/9ec04a7d8ebb1bbb9e3291503425cee1ec38a560/src/lib_generated.rs#L223

@dicej am I reading that right? Does it mean the Go os.ReadFile is trying to do more with the file than WASI allows?

[dicej]

@dicej am I reading that right? Does it mean the Go os.ReadFile is trying to do more with the file than WASI allows?

Possibly. What's interesting is that, although the "rights" system has been removed entirely from WASI Preview 2, this same issue happens there, also. Also, ERRNO_NOTCAPABLE doesn't appear in either the Preview 1 or Preview 2 source code, nor in the cap-std or system-interface crates on which they are based, so maybe it's coming straight from the OS? This will require some debugging, apparently.

[itowlson]

It might be informative to know if this happens (and if it has the same error number) on Windows or Linux; needless to say, Adam ran into it the very week I am away from my Windows/WSL machine...

[adamreese]

I tested on linux amd64 and got the same error

[kate-goldenring]

this is still an issue. Was able to repro on arm macOS

[lann]

Still an issue today, as reported by @asteurer

[lann]

Possibly related, though this specific issue is allegedly fixed: tinygo-org/tinygo#2382

[lann]

Also possibly related: bytecodealliance/wizer#24