Provide a julia.bat file in the installation directory of Julia on Windows

[KristofferC]

Background issue: JuliaLang/www.julialang.org#615.

Basically, to be able to start Julia from the terminal in Windows, one has to add the Julia-1.x.y/bin folder to PATH which I have understood is a bad idea because Windows also look in PATH for shared libraries to load for all applications (like LD_LIBRARY_PATH).

In a similar vein to the julia.bat file we create when compiling Julia on Windows, we could also distribute a julia.bat-file that is in the Julia installation directory. It would then be enough to add that directory to PATH (which doesn't contain any shared libraries).

cc @musm, do you think that is a reasonable idea?

[visr]

It would be good to have a directory that is safe to add to the Path. Would be even better if the installer offered to do it for you, just like for instance VS Code and Atom.

Note that I would currently not consider the installation root for safe, since uninstall.exe is also there.

For Anaconda, I now only add the 'condabin' directory to my path for safety, but this is not the standard yet.

[KristofferC]

Note that I would currently not consider the installation root for safe, since uninstall.exe is also there.

Good point.

[musm]

I'm not sure I agree with the suggestion here to ship a .bat file that opens up julia.exe.

The problem with adding the .bat is that it launches the exe from a cmd session and leads to annoying issues like microsoft/terminal#217

Python also dumps everything in the same folder like we do, although they don't use a bin folder and just place everything in the root folder.

Installing Julia through Chocolatey basically solves this problem and handles the upgrade issues in #34495 through the use of exe 'shims' (the issues in #34495 are mainly s related to 'package' level configuration). We should still try to improve things for those who don't use chocolatey.

[rapus95]

Well, I also could post that at the other issue (#34495) but I think it fits here more nicely as the other issue is more about automation of setup while this one is about better accessibility.
How about adding a new directory to the ~/.julia path, something like "exported_binaries" which will hold references(or executable scripts) to all binaries that should be accessible via the path. That'd have 3 advantages:
a) Once we fully arrive at shared libraries compiled from Julia it fits well into the workflow with artifacts and packages which are also placed in ~/.julia
b) Since ~/.julia is already a fixed and settled path it will be very simple to setup Julia compare to for example in the install directory which is subject to change dependent on user and Julia version. Thus, the location in PATH won't ever need to be updated again.
c) In case you uninstall Julia and have the ~/.julia directory still as a leftover (which currently is the default), we can provide further options. Especially we see that the user doesn't have a runnable julia executable in the common places -> Point to a new download or offer to delete the ~/.julia directory.

[KristofferC]

Python also dumps everything in the same folder like we do, although they don't use a bin folder and just place everything in the root folder.

While true, the only libraries there are python3.dll, python36.dll and vcruntime140.dll, while we have very many more.

We should still try to improve things for those who don't use chocolatey.

Yeah, that's the point of this issue. I would expect that a very small number of people use chocolatey to install Windows.

[musm]

While it seems like a good idea, is the dll issue a practical problem?

From https://docs.microsoft.com/en-us/windows/win32/dlls/dynamic-link-library-search-order?redirectedfrom=MSDN

The search order is as follows:

1. The directory from which the application loaded.
2. The system directory. Use the GetSystemDirectory function to get the path of this directory.
3. The 16-bit system directory. There is no function that obtains the path of this directory, but it is searched.
4. The Windows directory. Use the GetWindowsDirectory function to get the path of this directory.
5. The current directory.
6. The directories that are listed in the PATH environment variable. Note that this does not include the per-application path specified by the App Paths registry key. The App Paths key is not used when computing the DLL search path.

Basically we only search the PATH environment variable for shared libraries as a last resort.

[musm]

How hard would it be to have the julia.exe or the shared libs in a different folder?