Environment:

• splunk8.0
• splunk sdk 1.6.11
• python 3

When I create StreamingCommand "testcommand" with following code:

#!/usr/bin/env python
#-*- coding: utf-8 -*-
import sys
from splunklib.searchcommands import \
    dispatch, StreamingCommand, Configuration, Option, validators
import splunk
@Configuration()   
class TestCommand(StreamingCommand):
    def stream(self, events):   
        for event in events:        
            yield event
dispatch(TestCommand, sys.argv, sys.stdin, sys.stdout, __name__)

testcommand will hang when I use following SPL:
sourcetype=XXX| search url = "http://例子.卷筒纸" | testcommand

There has follwing error log in splunkd.log:

10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: During handling of the above exception, another exception occurred:
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: Traceback (most recent call last):
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: File "C:\Program Files\Splunk\etc\apps\XXXX\bin\testcommand.py", line 22, in
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: dispatch(TestCommand, sys.argv, sys.stdin, sys.stdout, name)
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: File "C:\Program Files\Splunk\etc\apps\XXXX\bin\splunklib\searchcommands\search_command.py", line 1118, in dispatch
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: command_class().process(argv, input_file, output_file)
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: File "C:\Program Files\Splunk\etc\apps\XXXX\bin\splunklib\searchcommands\search_command.py", line 435, in process
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: self._process_protocol_v2(argv, ifile, ofile)
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: File "C:\Program Files\Splunk\etc\apps\XXXX\bin\splunklib\searchcommands\search_command.py", line 787, in _process_protocol_v2
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: self.finish()
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: File "C:\Program Files\Splunk\etc\apps\XXXX\bin\splunklib\searchcommands\search_command.py", line 393, in finish
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: self._record_writer.flush(finished=True)
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: File "C:\Program Files\Splunk\etc\apps\XXXX\bin\splunklib\searchcommands\internals.py", line 775, in flush
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: self._write_chunk(metadata, self._buffer.getvalue())
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: File "C:\Program Files\Splunk\etc\apps\XXXX\bin\splunklib\searchcommands\internals.py", line 820, in _write_chunk
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: self._ofile.flush()
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: OSError: [Errno 22] Invalid argument
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: Exception ignored in: <_io.TextIOWrapper name='' mode='w' encoding='utf-8'>
10-25-2019 16:34:42.808 +0800 ERROR ChunkedExternProcessor - stderr: OSError: [Errno 22] Invalid argument