Splunk custom command ERROR ValueError: I/O operation on closed file

[Bhupal]

I've a custom command worked well with 8.2 and failing in 9.3 with the following error. Tried with both protocol version 1 and 2, i.e Intersplunk and Splunk SDK ways. 

Sharing of your experience and possible fix for this error would be much appreciated.  thank you in advacne.

03-15-2026 17:31:06.388 ERROR ScriptRunner [3954753 phase_1] - stderr from '/opt/splunk/bin/python3.9 /opt/splunk/etc/apps/botcop/bin/nndetailscmd.py':  Traceback (most recent call last):
03-15-2026 17:31:06.388 ERROR ScriptRunner [3954753 phase_1] - stderr from '/opt/splunk/bin/python3.9 /opt/splunk/etc/apps/botcop/bin/nndetailscmd.py':    File "/opt/splunk/etc/apps/botcop/bin/nndetailscmd.py", line 11, in <module>
03-15-2026 17:31:06.388 ERROR ScriptRunner [3954753 phase_1] - stderr from '/opt/splunk/bin/python3.9 /opt/splunk/etc/apps/botcop/bin/nndetailscmd.py':      results,dummyresults,settings = splunk.Intersplunk.getOrganizedResults()
03-15-2026 17:31:06.388 ERROR ScriptRunner [3954753 phase_1] - stderr from '/opt/splunk/bin/python3.9 /opt/splunk/etc/apps/botcop/bin/nndetailscmd.py':    File "/opt/splunk/lib/python3.9/site-packages/splunk/Intersplunk.py", line 359, in getOrganizedResults
03-15-2026 17:31:06.388 ERROR ScriptRunner [3954753 phase_1] - stderr from '/opt/splunk/bin/python3.9 /opt/splunk/etc/apps/botcop/bin/nndetailscmd.py':      results = readResults(input_str, settings)
03-15-2026 17:31:06.388 ERROR ScriptRunner [3954753 phase_1] - stderr from '/opt/splunk/bin/python3.9 /opt/splunk/etc/apps/botcop/bin/nndetailscmd.py':    File "/opt/splunk/lib/python3.9/site-packages/splunk/Intersplunk.py", line 275, in readResults
03-15-2026 17:31:06.388 ERROR ScriptRunner [3954753 phase_1] - stderr from '/opt/splunk/bin/python3.9 /opt/splunk/etc/apps/botcop/bin/nndetailscmd.py':      input_buf = TextIOWrapper(sys.stdin.buffer, encoding='utf-8')
03-15-2026 17:31:06.388 ERROR ScriptRunner [3954753 phase_1] - stderr from '/opt/splunk/bin/python3.9 /opt/splunk/etc/apps/botcop/bin/nndetailscmd.py':  ValueError: I/O operation on closed file

[PickleRick]

I'd take a guess that it's an issue with a python version incompatibility. 9.3 uses python 3.9 by default whereas earlier 9.x used 3.7 I think.

With 8.2 you probably could have still gotten away with python 2 so if your command used this it shouldn't work properly with Splunk 9.3.