Often I'll use tmux to start a task that will be running for a while. I will periodically go back and check on it using tmux -a and then disconnect if it still hasn't completed and check again later.Is there any way to just see a brief snapshot of what's going on in the session without fully attaching? I'm looking for something like theoretically doing a tail on the session to get the last bit of output ( but if I can avoid creating another file with a copy of the output all the better )Maybe attaching and having it immediately detach would also work. I'm attempting to save keystrokes, perhaps such a command could be executed remotely,i.e. ssh root@server tmux --tail ?
Can I see what's going on in a tmux session without attaching to it?
tmux
I think capture-pane might suit your needs:tmux capture-pane -pt $target-pane(see target-pane in the man page for the ways to specify a pane)By default, that command will dump the current contents of the specified pane. You can specify a range of lines by using the -S and -E options (start and end line numbers): the first line is 0, and negative numbers refer to lines from the panes scroll back history. So adding -S -10 gets you the most recent ten lines of history plus the current contents of the pane.tmux capture-pane -pt $target-pane -S -10The -p option was added in 1.8. If you are running an earlier version then you can do this instead:tmux capture-pane -t $target_pane \; save-buffer - \; delete-bufferBut mind those semicolons if you are issuing this command via ssh since the remote shell will add an additional level of shell interpretation (the semicolons need to be passed as arguments to the final tmux command, they must not be interpreted by either the local or the remote shell).