setterm -dumpN will dump the contents of the
screen of /dev/ttyN to a file screen.dump
in the current directory. See setterm(1).
The current contents of the screen of /dev/ttyN
can be accessed using the device /dev/vcsN
(where `vcs' stands for `virtual console screen').
For example, you could have a clock program that displays the
current time in the upper right hand corner of the console screen
(see the program vcstime in kbd-1.04.tar.gz).
Just dumping the contents goes with cat /dev/vcsN.
These device files /dev/vcsN do not contain
newlines, and do not contain attributes, like colors. From a program
it is usually better to use /dev/vcsaN
(`virtual console screen with attributes') instead - it starts with
a header giving the number of rows and columns and the location
of the cursor.
See vcs(4).