How can you trigger a render's execute command via opparm?

[Kardonn]

I've got a shader setup here that pulls textures based on .json lists and need to be able to swap that .json file during command line renders in order to generate preview images for material libraries. Problem is that the pre-render script [opparm /shop/shader json "S:/Lib/foo.json"] works, but that parm in a Houdini session runs a callback script when you hit enter after plugging in a .json path. When you change the .json path via opparm though...it doesn't get triggered and nothing in the shader actually updates.

There's an "update" button parm on the shader that runs the same callback script, I just don't know how to 'execute' that button from the pre-render script section of the ROP.

Anyone know how you do that?

[Kardonn]

Ignore me...another problem solved by the time tested approach called "read the f*cking manual".

Solution for anyone searching this thread for answers one day in the future:

opparm -C [node] [parm] [value]

The -C triggers any callbacks in addition to setting the parameter value.