I would like some programs, started from Xfce launchers, to open full screen. X has a "geometry" option but this allows only X and Y sizes to be specified, not full screen. I wrote a script that outputs the current screen's X x Y with the intention of using it in launcher commands.
Testing at the command line this worked:
/usr/bin/mrxvt -name c -geometry $(/home/c/d/bin/try/get_current_screen_size.sh) -ic /usr/share/pixmaps/mrxvt.xpm
so I pasted it into a launcher's command and it failed. On inspection it turned out that Xfce had silently removed the $.
I tried editing the /home/c/.config/xfce4/panel/launcher-<unique number>.rc file directly and it still did not work. Perhaps these files are loaded at session initialisation. Will try again after re-initialising the session and update this post.
EDIT: that didn't work. After re-initialising the session (actually a reboot for another reason), Xfce had re-written the /home/c/.config/xfce4/panel/launcher-<unique number>.rc file with the contents of the launcher (as viewed in the launcher's properties).
EDIT 2: logging out of Xfce and using a virtual terminal to edit the /home/c/.config/xfce4/panel/launcher-<unique number>.rc file did result in the $ appearing in the launcher command but it still didn't work -- presumably for the reason identified below by maybeway36 and David the H, that Xfce is not using a shell to process the command.