Internal Program Version: zvbi  0.2.44

With "video4linux" drivers, only one application at a time can capture
VB data.  The 2nd generation "v4l2" API allows multiple clients to
open a device, but still only one client may read from the device.  If,
for example, the Nxtvepg daemon runs in the background, users will not be
able to start a Teletext application.  The VBI proxy was developed as a
solution to this problem.

http://zapping.sf.net