Hostprocess (jobcontainers) containers cmd parsing fails

[jsturtevant]

I found using the CONTAINER_SANDBOX_MOUNT_POINT when cmd is the default shell doesn't work

I am adding a test that uses agnhost which hard codes its entry point to /agnhost (without an exe): https://github.com/kubernetes/kubernetes/blob/d64e91878517b1208a0bce7e2b7944645ace8ede/test/images/agnhost/Dockerfile_windows#L78

Since its hard coded I wanted to use the env to call the command but ended up with

image: jsturtevant/agnhost:2.33-1
command:
- "%CONTAINER_SANDBOX_MOUNT_POINT%\\agnhost"
- pause

 Error: failed to start containerd task "test": failed to start host process: exec: "C:\\C\\test\\agnhost": file does not exist: unknown

full yaml file: https://gist.github.com/jsturtevant/bf055cdd04cd93a9b62932a787ae5c77#file-doesnotwork-yaml

I was able to work around this by using start-process in the interm

[dcantah]

This was fixed with #1174. Doesn't have much to do with cmd as a shell, it's more that for exec.Cmd Go calls exec.LookPath which for the windows implementation uses a set of default file extensions to check against. The default logic is that the executable being asked to run has to have one of these extensions. It also checks the PATHEXT environment variable if you wanted to have it check for other types of file extensions. If you add a single space entry anywhere in the list of extensions for PATHEXT, it now will allow files with no extension to get through exec.LookPaths logic.

[jsturtevant]

I found the referenced fix does not work: kubernetes/kubernetes#120113 (comment)

When I exec into the job container it doesn't hat the PATHEXT set properly:

PS C:\hpc> echo "$env:PATHEXT"
.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC;.CPL;