You can make the busy cursor appear with:
Code:
xsetroot -cursor_name watch
And restore the standard pointer with:
Code:
xsetroot -cursor_name left_ptr
But I believe for a program to be able to display the wait cursor automatically on startup it has to be programmed to do it, usually with libstartupnotification.
You could, of course, try something like this:
Code:
#!/bin/bash
xsetroot -cursor_name watch&
your_binary
sleep 5
xsetroot -cursor_name left_ptr
exit
Which is ugly, but at least they will know something is happening...
~psi42