[PATCH 4 of 4] logtoprocess: drop support for ui.log() call with invalid msg arguments (BC)

[Yuya Nishihara]

On Thu, 15 Nov 2018 11:58:44 +0100, Boris FELD wrote:
> I'm +1 for always trying to format the message but could we continue to
> pass the other arguments ($MSG2, $MSG3)?
> 
> We are using log-to-process to monitor command execution time by reading
> `$MSG4` on the command finish.
> 
> Having only the formatted message would be more work as we will need to
> parse the formatted message to extract the useful information.

Perhaps the time value can be passed as a OPT_ variable?

> How would the new processlogger works, would we still have access to the
> message's arguments?

I'm going to drop the *msg argument. It could be passed in to logger.log(),
but I don't think it's correct to expose the *msg structure to users. If
we inserted some more %s parameters, $MSG{n} would be shifted. It can't be
stable.