[Sheepdog] [PATCH] configure: add urcu into configure

[Christoph Hellwig]

On Tue, May 08, 2012 at 04:32:16PM +0800, Liu Yuan wrote:
> From: Liu Yuan <tailai.ly at taobao.com>
> 
> It is suppoed to be used by sheepfs. Though sheep doesn't necessarily
> need this library, its well implemented atomic operation header will
> be put good use for other sheep code.

The configure check fails for me on Debian -testing with liburcu
0.6.7-2, even if the actual code using it compiles fine after reverting
the check.  The error message is:

checking for liburcu... no
configure: error: Package requirements (liburcu) were not met:

No package 'liburcu' found

Consider adjusting the PKG_CONFIG_PATH environment variable if you
installed software in a non-standard prefix.

Alternatively, you may set the environment variables liburcu_CFLAGS
and liburcu_LIBS to avoid the need to call pkg-config.
See the pkg-config man page for more details.

Does you check assume librcu prvoiding a .pc file?  At least on my
systems it doesn't seem to have one.