At the moment, I can open a PDF in Evince (say) by typing
$ evince document1.pdf
Then the command
$ evince document2.pdf
starts a second instance of Evince and opens the new document in that instance. This is not what I want. Instead, I want to be able to send a signal to the (running) instance that will make it open the new document in that instance. As far as I can see, this isn't possible with either Evince or XPDF.
I need to use a shell command (rather than File->Open) for scripting purposes.
Is there a piece of PDF software that will allow me to do this?
Motivation: The program TeXStudio is a TeX compiler, bundled together with a PDF viewer. When the user presses a button, the TeX source is compiled to PDF, and the PDF file is displayed in a separate window. If this window is already open, the program displays the PDF content in the existing window. I want to duplicate this functionality using tiled Vim and Evince windows in a tiling window manager, with appropriate plugins linking the two.