Junctions are nice, but I think they are limited to pointing to directories on local file systems. Symlinks can point to remote files and directories on local or remote file systems (including using UNC paths).
I didn’t bring up the windows permissions issue with symlinks because I think it is a stopper, I brought it up because we’ll need to include information about the minimal permissions needed to use the feature. It’s normal to request fine grained permissions for an application in a windows environment; I don’t think this would give anyone pause. Tim > On Dec 19, 2021, at 2:16 PM, Matt Sicker <[email protected]> wrote: > I think the NIO API for symlinks on Windows correspond to the ones that > require admin permissions to create. There are also file junctions that are a > feature of NTFS, though I’m not sure if there’s any way to create them > besides invoking cmd and running a mklink command from there (which, as it > might sound, requires a few layers of encoding to properly invoke). For more > info, take a look at > https://github.com/jenkinsci/jenkins/blob/master/core/src/main/java/hudson/os/WindowsUtil.java > > <https://github.com/jenkinsci/jenkins/blob/master/core/src/main/java/hudson/os/WindowsUtil.java> > where I first encountered this filesystem madness due to an old security > vulnerability we fixed in the Jenkins project years ago and ended up writing > most of the code I’m talking about. > -- > Matt Sicker > >> On Dec 19, 2021, at 08:33, Gary Gregory <[email protected]> wrote: >> >>> On Sun, Dec 19, 2021 at 9:03 AM Jochen Wiedmann >>> <[email protected]> wrote: >>> Having worked with symbolic links on Windows a lot, I find that >>> privileges are present, in most cases. However, there is the technical >>> question "How do I create them?" >> >> java.nio.file.Files.createSymbolicLink(Path, Path, FileAttribute<?>...) >> >> The API is documented as an optional operation so we might need a set >> of OS-specific calls to Runtime.exec(String). >> >> Gary >> >>> The best solution, that I have found so far is letting "cmd" do the >>> job for me. (The mklink command is not a separate executable, but >>> build into cmd.) >>> https://github.com/jochenw/afw/blob/master/afw-core/src/main/java/com/github/jochenw/afw/core/components/WindowsCmdSymbolicLinksHandler.java >>> Jochen >>> On Sat, Dec 18, 2021 at 7:43 PM Tim Perry <[email protected]> wrote: >>>> I like this idea, but I think it would require non-default permissions for >>>> the account the application runs under on windows. However, it could be >>>> feature that can be switched on. >>>> https://docs.microsoft.com/en-us/windows/security/threat-protection/security-policy-settings/create-symbolic-links >>>> Maybe I read the docs from MS incorrectly. >>>> Tim >>>>> On Dec 18, 2021, at 7:07 AM, Gary Gregory <[email protected]> wrote: >>>>> Hi All: >>>>> And now for something completely different. >>>>> I wonder why we do not do file rollovers like below, and if we should: >>>>> - Create the file with the target rolled over a name like applog-2021.txt >>>>> - Create a symlink for the constant name like applog.txt to point to >>>>> applog-2021.txt >>>>> - When it's rollover time, start writing to the new file >>>>> applog-2022.txt and change the symlink to point to it. >>>>> Zero copy. >>>>> Thoughts? >>>>> Gary >>> -- >>> Philosophy is useless, theology is worse. (Industrial Desease, Dire Straits)
