I'm working in Unity trying to launch Houdini with the HOUDINI_PATH and HOUDINI_PACKAGE_DIR value set,I wrote c# code to set the env variable before launching Houdini,but after the setting,Houdini can't be open,
so,I am trying to set it in the computer,not by code, just to check out why Houdini can't open,
and now,if I add HOUDINI_PATH with value like C:\a\b\c ,it shows error:

ERROR: Couldn't open resource file "resources" (No such file or directory)
= = = Houdini Package log = = =
Loading: C:/PROGRA~1/SIDEEF~1/HOUDIN~1.531/packages/kinefx.json

Loading: C:/PROGRA~1/SIDEEF~1/HOUDIN~1.531/packages/package_dirs.json
: Undefined variable ${HOUDINI_DISABLE_SIDEFX_PACKAGES} used in expression ${HOUDINI_DISABLE_SIDEFX_PACKAGES} == '1'
WARNING: Unsupported value for enable


Processing: C:/PROGRA~1/SIDEEF~1/HOUDIN~1.531/packages/kinefx.json

Processing: C:/PROGRA~1/SIDEEF~1/HOUDIN~1.531/packages/package_dirs.json

Resolved variables:
HOUDINI_PATH :
C:/PROGRA~1/SIDEEF~1/HOUDIN~1.531/packages/kinefx
C:/a/b/c

= = = = = = = = = = = = = = = =
WARNING: Found hotkey for context 'h.pane.parms' before the context definition
WARNING: Found hotkey for context 'h' before the context definition
Error running event handler:
Traceback (most recent call last):
File "kinefx::Sop/adapttoterrain, opdef:/kinefx::Sop/adapttoterrain?ViewerStateInstall", line 1, in <module>
File "C:\PROGRA~1\SIDEEF~1\HOUDIN~1.531\python37\lib\site-packages-forced\shiboken2\files.dir\shibokensupport\__feature__.py", line 142, in _import
return original_import(name, *args, **kwargs)
ModuleNotFoundError: No module named 'viewerstate'

Error running event handler:
Traceback (most recent call last):
File "kinefx::Sop/scenecharacterimport, opdef:/kinefx::Sop/scenecharacterimport?ViewerStateInstall", line 1, in <module>
File "C:\PROGRA~1\SIDEEF~1\HOUDIN~1.531\python37\lib\site-packages-forced\shiboken2\files.dir\shibokensupport\__feature__.py", line 142, in _import
return original_import(name, *args, **kwargs)
ModuleNotFoundError: No module named 'viewerstate'

Could not initialize the help server:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "C:\PROGRA~1\SIDEEF~1\HOUDIN~1.531\python37\lib\site-packages-forced\shiboken2\files.dir\shibokensupport\__feature__.py", line 142, in _import
return original_import(name, *args, **kwargs)
ModuleNotFoundError: No module named 'houdinihelp'

ERROR: Couldn't find 'FUSE_ColorOptions.ui' for reading. Looked in:
C:/PROGRA~1/SIDEEF~1/HOUDIN~1.531/packages/kinefx/config/Applications
C:/a/b/c/config/Applications

=======================================================================================================================

and if I add HODUINI_PACKAGE_DIR with value like :C:\a\b\c\package ,Houdini does not appear at all.
anyone can help to tell what is the standard about it.
thanks.

Hello,

In linux you can source houdini_setup and use $HH
(or anny other houdini environment variables)

In windows you cant use HCMD to launch Unity.

https://www.sidefx.com/faq/question/how-do-i-set-up-the-houdini-environment-for-command-line-tools/ [www.sidefx.com]

I`m not sure this is what you are trying to achieve.