How to defer output from sprintf? (only want to output a complete path + file)

So I have a patch where I first get a path to a folder, then attach this path to a bunch of filenames to read them into a jit.qt.movie.

I'm using (sprintf symout %s%s), which works great, except that the first time I load the folder path, it spits it out, and the jit.qt.movie generates an error.

Is there any way to defer output of the sprintf when I have only loaded the first argument? Or do I need to put something like a (trigger 1 s 0) connected to a gate to disable it while I load the first argument?