add screen

README.md

@@ -2456,12 +2456,17 @@ or
 tmux kill-session -t foo
 ``` 
 scroll:
+screeen
 Hit your screen prefix combination (C-a / control+A), then hit Escape.
 Move up/down with the arrow keys (↑ and ↓).
 
 Redirect output of an already running process in screen:
  (C-a / control+A), then hit 'H'
 
+store screen output for screen:
+Ctrl+A, Shift+H
+You will then find a screen.log file under current directory.
+
 Send command to all panes in tmux:
 ```bash
 Ctrl-B