cannot shell out to cmd's builtin commands

[jariou]

shell> cd works correctly

dir, set and path cause errors:

| | || | | | (| | | Version 0.3.0-prerelease+2224 (2014-03-30 00:26 UTC)
/ |__'|||__'_| | Commit 32c072e* (0 days old master)

shell> dir
ERROR: spawn: no such file or directory (ENOENT)
in _jl_spawn at process.jl:212

shell> set
ERROR: spawn: no such file or directory (ENOENT)
in _jl_spawn at process.jl:212

shell> path
ERROR: spawn: no such file or directory (ENOENT)
in _jl_spawn at process.jl:212

shell> cd
C:\Users\Jacques

[StefanKarpinski]

These are all Windows shell builtins, not commands. I'm not sure it really makes sense to try to reimplement all of these in Julia's REPL. You can't set environment variables in the UNIX shell either.

[jariou]

Ok,

I did not expect the REPL to reimplement shell functionality. I thought that the shell mode was a shortcut to save the user from having to type code like

run(cmd /C ???)

and that the implementation itself was essentially that under the cover.

I just tested it with the things I would mostly do in the shell, cd and dir. cd worked as expected and dir failed.

Forget I even mentioned it.

[StefanKarpinski]

It might make sense to just allow dir as an alias for cd on Windows. Not sure about the other ones. The idea is that you should be able to comfortably do stuff in shell mode without having to leave the Julia REPL. If these are really things that are needed to make things comfy on Windows, then perhaps we should consider it. Part of the problem, as I understand it, is that Windows doesn't really have a shell that you can reliably call, so we're just running code as-is. Also, I don't think this has anything to do with the new versus old REPL – they both behave the same way, as far as I know.

[jariou]

I did not know there was a shell mode in the original REPL

[StefanKarpinski]

It wasn't really a mode, but any input starting with ; was run as a command in the same way.

[jariou]

Ah! Didn't know that.

[jariou]

Is there a list somewhere of what shell "commands" are recognized?

[StefanKarpinski]

Yes: cd. That's it.

[tkelman]

@StefanKarpinski dir would be an alias to ls, not cd. This is part of a larger conversation about what "shell" should mean for Julia on Windows. One thing I ran into that I found quite cool, is there's a Win32 port of BusyBox: http://intgat.tigress.co.uk/rmy/busybox/index.html that would be a much lighter-weight alternative to bundling MSYS as we do now (due entirely to bundling Git, which may be replaced by libgit2 in the future).

[StefanKarpinski]

Ah, right. I should have known that (although I haven't used Windows since 1997). Yes, we definitely need a story for what "shell" means on Windows. Unfortunately, that's kind of a tough problem, it seems.

[vtjnash]

moving this out of 0.3, since it is a feature request not a bug