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From: Giorgos Keramidas <keramida@ceid.upatras.gr>
To: "Andrew Brampton" <brampton+freebsd-hackers@gmail.com>
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Date: Mon, 12 Jan 2009 18:17:38 +0200
In-Reply-To: <d41814900901120656s5d6f8f78te714fee01a6dff0f@mail.gmail.com>
	(Andrew Brampton's message of "Mon, 12 Jan 2009 14:56:21 +0000")
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Cc: hackers@freebsd.org, Eugene Grosbein <eugen@kuzbass.ru>
Subject: Re: Determine if a kernel is built with a specific option?
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On Mon, 12 Jan 2009 14:56:21 +0000, "Andrew Brampton" <brampton+freebsd-hackers@gmail.com> wrote:
> If you were going to do this, would you make it a configure flag... ie
> --enable-polling... That way it doesn't matter if the build box is
> different?

If both choices are available (i.e. no header files are missing, no
link-time libraries are unavailable, and so on), I'd probably make it a
runtime option:

  * A configure-time flag to set the 'default' and

  * A runtime option to explicitly specify the current preference when
    the program runs.

This seems a bit more flexible, and does not require an expensive ``go
back to your vendor, and ask for a special build-time option'' cycle to
test different setups when a field installation is done.