unix vncviewer - skipping intermediate screen states

Tjipto & Caecilia Sugijoto sugijoto "at" home.com
Tue, 19 Jun 2001 15:10:49 +0000


I am a student doing some analysis on VNC. Hope you can help...

I have two questions on the last bullet point of the feature list in README
file of vncviewer for UNIX.
In there it says:
"* Although still single-threaded, it behaves much like a multi-threaded
  The main thread of the program just dispatches VNC protocol messages.  X
  events are automatically processed whenever reading from the VNC
  would block.

  So for example, over a slow link, key and mouse presses are sent to the
  server even when drawing a screen update.  Previously they would only have
  been sent at the end of the update.  In some cases this can save time by
  skipping intermediate screen states."

1. What does single threaded but behaves like multi threaded mean ? I know
there is a event loop
that handles RFB messages, this reads any messages coming from vncserver and
"react" to it.
The thing I donot see is when and where it blocks and processes X messages.

2. When there is a series of keyboard or pointer events, they get sent one
at a time and as
such I donot see how it combines and skip inntermediate states.

I am testing the vncviewer(unix) with winvnc.

Thanks for your help.

To unsubscribe, send a message with the line: unsubscribe vnc-list
to majordomo "at" uk.research.att.com
See also: http://www.uk.research.att.com/vnc/intouch.html