Is it possible to `tail -f /dev/vcs`?

Question

I would like to get a continuous stream of output from the virtual terminal. Is that possible? If not, why is tail -f not working here?

Answer 1

The tail command is intended to work with regular files, where it can read the length of the file, seek to the end, and monitor the length as it grows. You cannot use it with a pipe or character special file, as on these files length is often meaningless and you cannot seek (though it may try to work).

The /dev/vcs character specials output a screendump of the virtual consoles, not a constant stream of data, so cat is no use and neither is tail. It simply outputs a screen dump (without newlines) and then EOF.

Converting this to a stream of output would be very difficult as you can only take a point in time view, and cannot tell from that what character stream has been sent to the console.