Solved! - Re: USRP UHD Source problem

With thanks to Christophe for his excellent advice, removing
~/.cache/grc_gnuradio/cache.json fixed things up. After needing to do
this now & then, I have a new gr heuristic:

if (weirdnessReigns) { delete cache.json; }

Thanks, Christophe!

Mike

On 4/24/21 2:55 PM, Mike Markowski wrote:
> Some progress.  When I log in as another user, gr runs fine with a usrp.
>  Logging in as me, I get the errors previously posted.  My environment
> seems to (suddenly) be the issue, so I:
>
> 1. Moved ~/.bashrc to a new name to avoid any improper env var settings.
>
> 2. Moved ~/.config/GNU\ RADIO
>
> But I still get errors previously posted.  Are there other files
> gnuradio-companion is looking at that could be the culprit?
>
> Thanks,
> Mike
>
> On 4/24/21 1:04 PM, Mike Markowski wrote:
>> Thanks for checking, Christophe.  I agree that it's strange.  I've
>> been away from gnuradio doing some cyclostationary work, so haven't
>> touched any flowgraphs in weeks.  I see that my newest flowgraphs were
>> built April 7 and that gnuradio-companion, no doubt after an Ubuntu
>> upgrade, shows a date of April 9.
>>
>> I'll share debugging breakthroughs, but would be glad to hear from
>> others if your GR 3.8.1.0 is or isn't running fine.  Most likely, it's
>> my environment since I don't see a flurry of 'me too' notes.
>>
>> Mike
>>
>> On 4/24/21 12:16 PM, Christophe Seguinot wrote:
>>> This flowgraph is correctly build under GR 3.9.0.0 (no USRP source to
>>> test further)
>>>
>>> The error is quite strange, I think there is no "len_tag_name"
>>> parameter in such a simple flowgraph
>>>
>>> On 24/04/2021 16:35, Mike Markowski wrote:
>>>> I'm running gnuradio companion 3.8.1.0 (Python 3.8.6) on Ubuntu
>>>> 2020.10.  After a few weeks away from gnuradio, today I get errors
>>>> with the USRP UHD Source, and previously working flowgraphs no
>>>> longer build. (Previously built flowgraph python files still run
>>>> fine.)  The attached flowgraph doesn't get much simpler, but
>>>> building yields:
>>>>
>>>> Generating: '/home/mm/sdr/fm/uhdTest.py'
>>>> Generate Error: (NameError("'len_tag_name' is not defined"),
>>>> 'uhd.usrp_source(\n    ",".join((${dev_addr}, ${dev_args})),\n
>>>> uhd.stream_args(\n        cpu_format="${type}",\n
>>>>
>>>> [... on and on ...]
>>>>
>>>> , uhd.ALL_MBOARDS)\n% else:\n# No synchronization enforced.\n%
>>>> endif\n')
>>>> >>> Failure
>>>> Traceback (most recent call last):
>>>>   File "memory:0x7f3082ab36d0", line 136, in render_body
>>>>   File "/usr/lib/python3/dist-packages/mako/runtime.py", line 106,
>>>> in __getitem__
>>>>     return compat_builtins.__dict__[key]
>>>> KeyError: 'len_tag_name'
>>>>
>>>> [... still more...]
>>>>
>>>> Is anyone else seeing this error?
>>>>
>>>> Thanks,
>>>> Mike
>>>