The "shell mode" in the REPL is not fully functional on Windows

[PetrKryslUCSD]

I know that this is not the fault of Julia, but the Windows shell does not play nicely with Julia in the "shell mode". For instance, typing ; dir will result in an error because this is not a command executed by program. This applies to most of the commands available in the Windows shell. So far I found only tree and help to work...

It would probably prevent some useless experimentation and disappointments for new users if this fact was clearly mentioned in the documentation: the "shell mode" does not work in Windows.

[yuyichao]

All commands (programs) should work. If you don't have any that's what "working" should be like so we would definitely not call it "not work".

[PetrKryslUCSD]

Sorry: what???c

[TotalVerb]

As mentioned, dir is not a program on Windows, which is why you cannot use it in shell mode. You can use instead cmd /e dir.

[TotalVerb]

I don't think it's correct to say the shell mode is not fully functional on Windows, but it is perhaps worth mentioning that on all operating systems, the shell is not necessarily bash or cmd and as such does not necessarily have support for bash or cmd builtins which are not actual programs. (For instance, on Linux I believe it uses /bin/sh, which is dash on Debian systems and dash supports a proper subset of bash builtins.)

[yuyichao]

Also note that the shell mode is not a native shell and is not meant to be so you shouldn't expect all shell (cmd) features to be available. I have no idea why dir is implemented as a builtin rather than a program but AFAIK it is so you won't be able to run any of them by design.

It was also decided against calling cmd automatically on windows since IIUC it has really weird escape/quoting behavior (again, I'm not exactly sure what those are but others might be able to give you examples). Powershell was also an option but IIUC availability was not as clear.

Still I agree the expectation should be documented and hence the doc label. It just shouldn't be called "not working".

[yuyichao]

Ref link discourse thread and I should clarify that my first comment assumed prior knowledge from that thread https://discourse.julialang.org/t/dir-does-not-work-in-the-console/5732/4?u=yuyichao (i.e. dir is not a program).

[PetrKryslUCSD]

@yuyichao is right, the code IS actually working as designed. Nevertheless, it will be a disappointment to those who expect the shell mode to be as usable on Windows as it is on Linux. Hence it may be better to be upfront about it in the documentation.

[stevengj]

See #21294 — it would be nicer to use cmd by default on Windows.

[devel-chm]

I'm new to Julia using win64 version 6.2 and just discovered that the Julia REPL "shell" mode doesn't work on windows, apparently by design. I have a few thoughts on this from my own experiences:

• At the least this is a documentation and usability issue: there was nothing in my initial reading of the docs to suggest that shell mode doesn't work on windows. I would describe it as "seems to fall back to an exec mode rather than a shell mode".
• Perhaps the mode name could be changed to exec> rather than shell> if that is the functionality actually being provided in "shell mode".
• Please don't hardwire in a specific cmd or powershell option. It should be the users choice as sometimes either one may not be available (or neither one!).

[PetrKryslUCSD]

The only solution on Windows so far is to run julia from within git bash. Then all the shell commands work
properly. Setting JULIA_SHELL never worked on Windows AFAICT.

[stevengj]

It doesn't work because #23703 or similar was never merged.

[devel-chm]

Thanks for the tip. It appears to work from within the cygwin bash as well. I still think better documentation and some work to avoid confusion and unnecessary differences between the underlying hardware a software would be a good investment.

[stevengj]

I think it would be good to have an actual shell mode in Windows, rather than a "shell" mode that is not running any real shell.

[epogrebnyak]

@stevengj - I totally side with this expectation, if it called a shell it better be a shell.

On my side tree, help and cd are working, while echo and dir do not:

shell> echo 1
ERROR: IOError: could not spawn `echo 1`: no such file or directory (ENOENT)
Stacktrace:
 [1] _jl_spawn(::String, ::Array{String,1}, ::Cmd, ::Tuple{RawFD,RawFD,RawFD}) a
t .\process.jl:367
 [2] (::getfield(Base, Symbol("##495#496")){Cmd})(::Tuple{RawFD,RawFD,RawFD}) at
 .\process.jl:509
 [3] setup_stdio(::getfield(Base, Symbol("##495#496")){Cmd}, ::Tuple{RawFD,RawFD
,RawFD}) at .\process.jl:490
 [4] #_spawn#494(::Nothing, ::Function, ::Cmd, ::Tuple{RawFD,RawFD,RawFD}) at .\
process.jl:508
 [5] _spawn at .\process.jl:504 [inlined]
 [6] #run#505(::Bool, ::Function, ::Cmd) at .\process.jl:652
 [7] run at .\process.jl:651 [inlined]
 [8] repl_cmd(::Cmd, ::REPL.Terminals.TTYTerminal) at .\client.jl:77
 [9] top-level scope at none:0