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You can invoke the script using the following environment variable and specifying a value of 1.

Shader names can be used to namespace or version your hdas. Prefix before the first _ will become the namepace and the numerical suffix after the last _ will become the version. For example, a shader file called namespace_myshader_2.osl will be namespace::myshader::2 in Houdini. This can allow you to have multiple versions of a shader in your scene and not have to worry about naming your shader the same as a third party asset or houdini node. See a more detailed explanation of digital asset namespacing and versioning here. 

Once the script is run on Houdini startup, it will save the resulting HDA files in the default user directory unless otherwise specified. You can change this location by setting RFH_USER_PREF_DIR. If this isn’t set, the HDAs will be saved in HOUDINI_USER_PREF_DIR.

Once these have been created, you can reuse them by resetting the RFH_ARG2HDA environment variable to 0, otherwise this will run each time you start Houdini and update the nodes automatically. This can be desirable unless there are many nodes causing a slow startup or no updates are being made that need to be captured each startup.

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-V myVersionNumber, adds version to shader, see SideFX explanation of versioning here.

Verbose

-v, output debug messages