I’m using Port.open to execute some npm tools. This works fine on macOS and Linux but fails on Windows with the following reason: * (ErlangError) erlang error: :eacces erlang.erl:2080: :erlang.open_port({:spawn_executable, "/path/to/node_modules/.bin/concisecss.cmd"}, [:exit_status, :stderr_to_…

Answering myself here with the solution. The problem was that cmd scripts can’t be spawned as executables on Windows, so I had to use cmd.exe. I looked at the :os.cmd sources to see how Erlang does it and found the winning combination. In the end, the answer was to use cmd.exe /c foo.cmd, but with …

Elixir Programming Language Forum

Port.open EACCES on Windows

Questions / Help

Nicd May 24, 2017, 7:58am 5

Ah yes, that is a big problem. I need the output for logging.