> Jamie, if there is a way to sync on the X server actually completing its > work, then we could do that instead.
xscreensaver-command uses XSendEvent to send the ClientMessage to xscreensaver; it then waits up to 10 seconds for a response message to be written to the window. However, that the response is sent when xscreensaver has *begun* the process of blanking the screen, not after. It's probably only a few hundred instructions, but there are a couple of X11 round-trips before that window shows up. Also recall that if the user has "fade" turned on, blanking the screen could involve a multi-second animation. -- Jamie Zawinski https://www.jwz.org/ https://www.dnalounge.com/
