elm-repl fails in directories inside a smbfs mount

[mexx]

If I change into a directory inside a smbfs mount, elm repl doesn't work properly.

$ elm repl
---- elm repl 0.16.0 -----------------------------------------------------------
 :help for help, :exit to exit, more at <https://github.com/elm-lang/elm-repl>
--------------------------------------------------------------------------------
> 1+1
elm-repl: repl-temp-000.elm: openFile: does not exist (No such file or directory)

Couldn't the file repl-temp-000.elm be created in /tmp or ~ instead?

[lynn]

I’m facing a similar problem: elm-repl: repl-temp-000.elm: openFile: permission denied (Permission denied). If the file can’t be created elsewhere, then at least a helpful error message would be cool.

[wjdhamilton]

👍

[Benxamin]

Permissions issue.

When I installed the Elm-Platform-0.17.1.pkg , it asked for my admin password and installed the elm apps in /usr/local/bin/ owned by user "root" with group "wheel". Everything else I run is user "my username" group "admin". I changed everything in that directory that started with 'elm' to those my permissions, and restarting iTerm2, it worked.

I found this directory by running which elm-repl

[dtonhofer]

@Benxamin I changed everything in that directory that started with 'elm' to those my permissions, and restarting iTerm2, it worked.

Hmmm... downgrading the security/sanity of the installation (i.e. changing the ownership of a globally installed package to those of a particular user) so that things work does not sound like the correct way to go about things.

elm-repl wants to create working files in the "current working directory" (of the shell that started elm-repl). If that directory is not writeable by the current user, then it bails.

This can be seen by attaching strace to the elm-repl process (strace -p <pid>), then executing 1 / 2 for example.

The system call failure to write a temporary file

openat(AT_FDCWD, "repl-temp-000.elm", O_WRONLY|O_CREAT|O_NOCTTY|O_NONBLOCK, 0666) = -1 EACCES (Permission denied)

is seen if one is in a non-writeable directory (ouch). AT_FDCWD means "create file in current working directory".

So you have to run a script that creates a working directory; cds to it, then launches elm-repl, something like:

D=elm-repl-tmp; cd ~ ; [[ -d $D ]] || mkdir $D ; cd $D ; elm-repl

The above creates elm-repl-tmp in your home directory and starts elm-repl in there. The directory is immediately filled with 1.7 MiB of stuff.

elm-repl should really deal with this and create a user-specific working directory all by itself, something by default underneath /tmp/$(whoami) and accessible to the current user only for example, or else allow defining the working directory on the command line, or both.

(elm-repl 0.18.0 on node v9.11.1 here, on Linux Fedora 27, btw.)