Is it at all possible to just run Photoshop in the command line with no GUI ever getting loaded?
No. The best you can do is run it with all of the panels hidden and then use the OS to 'hide' the application. This works out pretty well on the Mac, not quite so good on Win.
Also, a one line script can be used to shutdown PS.
executeAction(charIDToTypeID('quit'), new ActionDescriptor(), DialogModes.NO);
Thanks. I'm on Windows, but I'll try that out anyway.
The code won't work since I'm not actually using Photoshop's scripting - I am using Java. I don't think PS scripting would allow 90% of what my script/program does. Thanks anyway.
The code won't work since I'm not actually using Photoshop's scripting - I am using Java
If you want the droplet to shutdown PS before it's done, do an 'Insert Menu Item' and add 'File > Exit' as the last step in the action and resave the droplet. No need for JS.
On windows I would control Photoshop via VBScript or any OLE Automation supported language and set the visible property
app.visible = true