screen: Lock

 
 8.3 Lock
 ========
 
  -- Command: lockscreen
      ('C-a x', 'C-a C-x')
      Call a screenlock program ('/local/bin/lck' or '/usr/bin/lock' or a
      builtin, if no other is available).  Screen does not accept any
      command keys until this program terminates.  Meanwhile processes in
      the windows may continue, as the windows are in the detached state.
      The screenlock program may be changed through the environment
      variable '$LOCKPRG' (which must be set in the shell from which
      'screen' is started) and is executed with the user's uid and gid.
 
      Warning: When you leave other shells unlocked and have no password
      set on 'screen', the lock is void: One could easily re-attach from
      an unlocked shell.  This feature should rather be called
      'lockterminal'.