I don't know how to make an interface for this, but somehow the user needs to be able to switch which shader they're looking at. The quickest dirtiest solution I can think of would be a python script that runs glslViewer with a "baked" shader. Then the fragment/vector shaders are hot-swapped by python overwriting the baked file, and glslViewer's file watcher would just continue along. But in an ideal situation, a shader using backbuffer feedback switching back and forth with another shader with feedback would result in painting the screen continuously without it resetting. And I'm not sure if that's possible.
I don't know how to make an interface for this, but somehow the user needs to be able to switch which shader they're looking at. The quickest dirtiest solution I can think of would be a python script that runs glslViewer with a "baked" shader. Then the fragment/vector shaders are hot-swapped by python overwriting the baked file, and glslViewer's file watcher would just continue along. But in an ideal situation, a shader using backbuffer feedback switching back and forth with another shader with feedback would result in painting the screen continuously without it resetting. And I'm not sure if that's possible.