Honeybee - No module named fcntl


I just got Honeybee and Ladybug installed. The Honeybee core library component is throwing an error:

        {0;0}<br/>0. Runtime error (ImportException): No module named fcntl<br/>1. Traceback:<br/>  line 431, in &lt;module&gt;, "C:\Python27\Lib\subprocess.py"<br/>  line 78, in script<br/><br/>

I’m on a Windows10 OS.

I’ve added a lil’ screen shot so you can see exactly what I’m looking at.

Any thoughts?

thank you!


Hi David,

Can you open the attached file and send me a screen capture of the output. Your component is trying to load subprocess from Python and not IronPython library. Attached file outputs path to sys.path and PYTHONPATH on your system.


PythonPath.gh (3.98 KB)

Hi Mostapha,

thanks. Here is the screenshot from PythonPath.gh.


It is true that there is no PYTHONPATH env variable set.

Sorry. I should have tested them one by one. Can you try the attached file instead. We may need to overwrite sys.path on your system.

PythonPath_1.gh (3.43 KB)

        {0;0}<br/>0. C:\Python27\Lib<br/>1. c:\Program Files\Rhinoceros 5 (64-bit)\Plug-ins\IronPython\Lib<br/>2. C:\Users\buildlab\AppData\Roaming\McNeel\Rhinoceros\5.0\Plug-ins\IronPython (814d908a-e25c-493d-97e9-ee3861957f49)\settings\lib<br/>3. C:\Users\buildlab\AppData\Roaming\McNeel\Rhinoceros\5.0\scripts<br/><br/>

Thanks. That shows why it’s happening. For some reason you have Python27 as the first item. This should be fixed in GHPython but for now we can move import sys up as the first import and then sort sys.path by Python27 to make sure it will be moved to the bottom of the list.

import sys
sys.path = sorted(sys.path, key=lambda p: p.find(“Python27”))

Attached file has a modified Honeybee_honeybee component. Let me know if the component executes with no issues and we can add this as part of the official release.


Honeybee_PythonPath_reversed.gh (73.5 KB)


yes - that seems to have made it happy:

  <br/>17. Hooohooho...Flying!!<br/>Vviiiiiiizzz...<br/><br/>

Great! Thanks for checking. I pushed the modified honeybee_honeybee to github. I hope it doesn’t happen but you may need to update honeybee and ladybug to avoid version conflicts.

hey mostapha!

I am having the same issue with ladybug.

This is what is showing up with the same runtime error (importexception). Could you please help me?

appreciate your help! thank you!


C:\programfiles\rhinoceros 5 (64-bit)\plug-ins\ironpython\lib

C:\users\haowen wu\appdata\roaming\mcneel\rhinoceros\5.0\plug-ins\ironpython (814d908a=e25c-493d-97e9-ee3861957f49)\settings\lib

C:\users\haowe wu\appdata\roaming\mcneel\rhinoceros\5.0\scripts

Hi Rebecca, Which version of Ladybug are you using? Can you post the full error message?


I think I am having a similar issue with Ladybug and Honeybee. The same error message is appearing from previous posts. See attached screenshot

Many thanks