`failed to access temp dir /pprof: mkdir /pprof: Access is denied.` on Windows when PPROF_TMPDIR is not set about pprof

[nolanmar511]

Based on our documentation, we should be using "%USERPROFILE%/pprof" on windows when no value is set for PPROF_TMPDIR.
Just to double check, do you know if there was a value for %USERPROFILE% when you had this error?

[realityexists]

Yes, I have %USERPROFILE% set. It's easily reproducible by running go tool pprof blah - it doesn't seem to matter whether the file "blah" exists or not.

[nolanmar511]

I've tried running the latest version of pprof, with go version 1.8.3, on a Windows machine when %PPROF_TEMPDIR% is not set. However, I wasn't able to replicate this error.

Do you how recent your version of pprof is, or if this problem persists for you with the latest version? Could it be related to your version of windows (I ran this on a computer with Windows 10 Home)?

[aalexand]

Note that the user runs go tool pprof myfile.prof here, which uses pprof that is part of Go distribution.

[aalexand]

Maybe this is golang/go#18864 which was fixed in #95?

[realityexists]

Yes, it looks like the same issue to me. I would still suggest checking that whatever environment variable you picked is not empty before appending a sub-path to it. Doing that would have given a clearer error here. Also, in one case filepath.Join(os.Getenv(homeEnv()), ... is used and in another case os.Getenv(homeEnv()) + "/pprof" - not sure if that's safe on Windows.

[aalexand]

Using filepath.Join() consistently and not using empty string as an absolute path prefix are all reasonable things, yes.