Claudio Girardi - 2018-02-19

Hello,
I've just verified with Qucs 0.0.19 on Linux and the File based voltage source behaves as you expect to: if you select a file which resides in the project directory, only the filename is shown, without the full path.
Did you create a project to hold all the Qucs files? It should be a directory ending in "_prj" but I do not see such a directory name in the file path for the VFile component you are using.