Lookuperror: unknown encoding: cp949 about ironpython3

[slozier]

The command line and C# program could have different default encodings. What value does f.encoding give you?

Is your file really using the cp949 encoding? If not you could pass in an explicit encoding, for example if it's utf-8: open(path, 'r', encoding='utf-8').

cp949 is not available because we don't have an implementation for _codecs_kr. Related issue: IronLanguages/ironpython2#659

[nalsandori]

• I excuted the following commands in each program respectively.
  >>>sys.getdefaultencodnig() --> 'utf_8'

• The same results were displayed on both the ironpython console and c# program

• The following code also causes an encoding error in c# program(based on ironpython 3.4.1)
  os.popen(uabswitchcmdpath + ' -v').read()
  --> the above command worked fine in a c# program based on ironpython 2.7.9

• Here is the c# initialize code

var runtime = IronPython.Hosting.Python.CreateRuntime();
runtime.IO.SetErrorOutput(streamwriter, Encoding.Default);
runtime.IO.SetOutput(streamwriter, Encoding.Default);
runtime.IO.SetInput(streamwriter, Encoding.Default);

[slozier]

sys.getdefaultencoding() is not the encoding used by open. You can use locale.getpreferredencoding(False) to get that value, or open(filename).encoding.

You could also try utf-8 mode which causes open to default to utf-8:

var runtime = IronPython.Hosting.Python.CreateRuntime(new Dictionary<string, object> { { "Utf8Mode", true } });

[nalsandori]

Thank you very much for your kind explanation.
The c# code has been helpful to me