Re: [PATCH 2.6.25-4] getdelays.c: signal handling for log rotation

[Scott Wiersdorf]

On Fri, Jun 06, 2008 at 03:59:09PM +0200, Andi Kleen wrote:
> Scott Wiersdorf <scott@xxxxxxxxxxxx> writes:
> 
> > This adds a USR1 signal handler to getdelays.c, which causes getdelays
> > to close its logfile and reopen it (if '-w logfile' is
> > specified). This is useful in situations when getdelays is running for
> > a long time (i.e, the log file growing) and you need to rotate the
> > logs but don't want to lose any log data.
> 
> You could do the same by sending SIGSTOP; copy file; truncate file; SIGCONT

I believe it, but you can miss a lot of important stuff between STOP
and CONT, especially on a busy system. With a single handler that
reopens the file, you'll miss at most one netlink datum packet, and
most of the time you'll miss nothing.

Scott
-- 
Scott Wiersdorf
<scott@xxxxxxxxxxxx>
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