capture tor log messages before control connection is opened
While working on ticket legacy/trac#9675 (moved), Kathy Brade and I discovered that the tor log warnings regarding clock skew are sometimes generated very early as tor starts up. Unfortunately, there is a known problem in Tor Launcher where tor log messages are not captured until Tor Launcher is able to connect to the control port and issue a SETEVENTS command (the Mozilla process control APIs do not provide a way to capture stdout or stderr).
One solution is for tor to provide a way to retrieve old log messages (e.g., a new getinfo command) or otherwise provide a way to capture messages that are generated before a control connection is opened. Another option for this specific scenario would be to modify tor to ensure that clock skew is always reported via the status/bootstrap-phase mechanism.