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Subject: Re: [PATCH 5/6] mm: add some KERN_CONT markers to continuation
 lines
From: Joe Perches <joe@perches.com>
To: Linus Torvalds <torvalds@linux-foundation.org>
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Date: Tue, 01 Mar 2011 21:28:00 -0800
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On Tue, 2011-03-01 at 13:46 -0800, Linus Torvalds wrote:
> the concept of
>     printk(KERN_CONT "\n")
> is just crazy: you're saying "I want to continue the line, in order to
> print a newline". Whaa?

It's a trivially useful "end of collected printk" mark,
which was made a bit superfluous by the code that added
any necessary newline before every KERN_<level>.

There are a thousand or so of them today.

$ grep -rP --include=*.[ch] "\b(printk\s*\(\s*KERN_CONT|pr_cont\s*\(|printk\s*\()\s*\"\\\n\"" * | wc -l
1061

That code made all message terminating newlines a bit
obsolete.  I won't be submitting any patches to remove
those EOM newlines any time soon.

I hope no one does that.

It would be actually useful to have some form like:

	cookie = collected_printk_start()
loop:
		collected_printk(cookie, ...) (...)
	collected_printk_end(cookie)

so that interleaved messages from multiple
concurrent streams could be sensibly collected
either post processed or buffered.

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