The docs mention that pythonrc.pywill be automatically executed if placed in pythonX.Ylibs/ folder (source [www.sidefx.com]).

The massive downside for this approach is that if I have the exact same pythonrc.pyfor multiple houdini versions that use different python versions, I now need to make multiple pythonX.Ylibs folders with identical copies of the script.

Is there any way to make Houdini recognize it and execute it from a custom folder? I tried adding my package folder to $PYTHONPATH, as well as the scripts folder without success.

The docs are incorrect (or outdated)!

You can place pythonrc.py, ready.py and uiready.py in the more generic HOUDINI_PATH/scripts/python/ locations and they will be executed.

For example, I have a generic $HOME/houdini directory added to my HOUDINI_PATH

As a followup, what the docs also don't mention is that unless you really do have a need for different files for different Python versions, the only other real usecase for putting things in pythonX.Ylibs folders is that it's the only way you can currently override shipped Houdini modules in the $HH/pythonX.Ylibs folder.

Because of how Houdini sets up sys.path at startup time, $HH/pythonX.Ylibs will always come BEFORE any $HOUDINI_PATH/scripts/python entries, but AFTER any $HOUDINI_PATH/pythonX.Ylibs locations. This means that if you need to override anything in $HH/pythonX.Ylibs, you need to have your overridding modules in a pythonX.Ylibs folder.

I've definitely been guity of this too in the past until figuring it out and I generally put all my stuff under scripts/python now, expect when needing the specific overridding behavior such as using a custom nodegraphhooks.py to add network editor events

It works! Thank you Graham, that is a lot of amazing info.

I now see that the docs do mention this path one time, but it's very easy to miss.

Hi everyone,

I wanted to add a small follow-up to Graham's post for anyone transitioning to Houdini 21 (21.0.596 in my case).

In my previous setup, I was using the environment variable HOUDINI_SCRIPT_PATH to point to my startup modules, including uiready.py. However, in H21, I found that uiready.py was failing to execute from that location.

As Graham pointed out, the most reliable way now is to move these scripts into:
$HOUDINI_PATH/scripts/python/uiready.py

It appears that in H21, uiready.py has effectively been integrated into the standard startup sequence logic. If you define it via HOUDINI_SCRIPT_PATH, it might be ignored or superseded by the internal lookups.

By following Graham's suggestion the execution becomes consistent again, thanks to Graham for the tip!