Re: Search paths for configuration files

From: David Abrahams (dave_at_[hidden])
Date: 2005-02-10 07:21:14

Vladimir Prus <ghost_at_[hidden]> writes:

> On Wednesday 09 February 2005 19:43, David Abrahams wrote:
>> On linux we search /etc for the site-config.jam. Doesn't something
>> under /usr/local (maybe /usr/local/etc) seem like it should be
>> searched too?
>
> I don't think so:
> http://www.pathname.com/fhs/pub/fhs-2.3.html#THEUSRHIERARCHY
> says:
>
> /usr is the second major section of the filesystem. /usr is shareable, 
> read-only data. That means that /usr should be shareable between various 
> FHS-compliant hosts and must not be written to. Any information that is 
> host-specific or varies with time is stored elsewhere.
>
> So, /usr is not for any configuration files at all.

I'm not sure what that "should not be written to" means. How are you
supposed to install software then? If you read the description of
/usr/local it certainly sounds like it's shareable, host-specific, and
varies with time.

I think you're probably right, as I've never understood this stuff
well (I'm going to read that link now), but the descriptions sure are
confusing.

>> On all systems we search $BOOST_BUILD_PATH. But the build system may
>> not be installed in $BOOST_BUILD_PATH (because its location is
>> specified by boost-build.jam). Shouldn't we look in the build system
>> directory first?
>
> I believe that path specified by boost-build.jam is prepended to 
> BOOST_BUILD_PATH.

Not from the user's perspective it isn't. The environment variable is
not changed. That prepending is just an internal hack we do to our
copy of the variable as part of the initialization process. In fact
we don't even mention it IIRC (and we shouldn't).

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com