saving xterm scrolling data to file

[brownh@hartford-hwp.com (Haines Brown)]

When I run a command with debug in xterm, a lot of info scrolls
past. How can I save this to a file? All I get is how to debug
the debug message, not the debuging information itself, which just
scrolls quickly by in the terminal:

  For debugging messages, please use the --debug option.
  Debugging messages may help finding a solution to your problem.
  If you intend to send any error or debug messages to the gphoto
  developer mailing list <gphoto-devel@lists.sourceforge.net>, please run
  gphoto2 as follows:

    env LANG=C gphoto2 --debug --debug --debug -f "/opt/tmp/camera" -P

  Please make sure there is sufficient quoting around the arguments.

I vaguely recall there is a utility to capture input to the terminal
to file.