Re: [libvirt] [PATCH] dynamic debug patch
On Wed, Nov 05, 2008 at 08:15:31PM +0000, Daniel P. Berrange wrote:
On Wed, Nov 05, 2008 at 08:49:23PM +0100, Daniel Veillard wrote:
> Okay, that's an API, expecting the app will use it. What i want is
> allow debug without the application being modified which is rather
> different.
I don't think libraries have any business hooking into application
signal handlers, because each app has its own preferred debugging
infrastructure.
And sometimes you just can't expect the app to pass it. SIGUSR2
is hooked in gamin library, which for quite a while was linked to
all desktop apps. This never raised any problem, but allowed to get
debug informations in situations where it's hard to activate a logger.
The more complex the interaction of the library with the system the
more it's useful to have this kind of debugging available in my opinion.
In Java, you'd want to hook all this info into log4j,
You're still thinking in terms of application driven logging, and
this mechanism is different. They suit different purpose.
Daniel
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