I wish this worked without prefixing the commands with "once". Especially if I ran a command with verbose output and afterwards decided I wanted to grep something from it. Terminals have the output in their scrollback buffer and maybe it's just a matter of writing an "output" command that lets me run:

    $ cmake ..
    $ output | grep "libssl version"

You could probably achieve something like that using Fish shell and their fish_preexec and fish_postexec event hooks.

Edit: Nope, looks like you can't. You only get the invoked command and no output.