Confirm file successfully written to or not - troubleshooting Julia/Plots/CI issue

[BioTurboNick]

Hello,

I'm having a problem in GitHub CI via Plots.jl in Julia, where the issue seems to be that gr fails to create the file, or doesn't create the file at the expected location. But there's no error raised from this part. The only trouble comes when Plots tries to read from that temporary file and copy it to the output file, because the expected file doesn't exist.

It only happens in CI and not on my local machine. And only seems to occur in Julia 1.8.2+.

Is it possible to detect a file IO error, or to get printed debug information (e.g., tell me where it saved a file to), without rebuilding anything?

Does it rely on Julia's libuv to write to the file? (I ask because there was a bump in that library's version between 1.8.1 and 1.8.2).

[jheinen]

I have observed similar problems some weeks ago when removing temporary files on Windows systems. I have not been able to find out the exact reason and have changed the test environment and removed the rm commands in the Julia scripts.

I'll be back in the office starting next Tuesday and will be adding more debug statements to the GR run-time. Nevertheless I/O bugs should be reported in the current version though.