Re: [Boost-build] user-config.jam permanent location

Subject: Re: [Boost-build] user-config.jam permanent location
From: Vladimir Prus (ghost_at_[hidden])
Date: 2010-08-14 13:35:23

On Saturday 14 August 2010 17:40:24 Edward Diener wrote:

> On 8/14/2010 1:43 AM, Vladimir Prus wrote:
> > On Saturday 14 August 2010 06:01:58 Edward Diener wrote:
> >
> >> On 8/13/2010 2:39 AM, Vladimir Prus wrote:
> >>> On Friday 13 August 2010 07:16:21 Edward Diener wrote:
> >>>
> >>>> When I open any user-config.jam I see:
> >>>>
> >>>> "#   This file is used to configure your Boost.Build installation. You
> >>>> can modify
> >>>> # this file in place, or you can place it in a permanent location so that it
> >>>> # does not get overwritten should you get a new version of Boost.Build. See:
> >>>> #
> >>>> #
> >>>> http://boost.org/boost-build2/doc/html/bbv2/reference.html#bbv2.reference.init
> >>>> #
> >>>> # for documentation about possible permanent locations."
> >>>>
> >>>> When one goes to
> >>>> http://boost.org/boost-build2/doc/html/bbv2/reference.html#bbv2.reference.init
> >>>> there is no information there about a permanent location for
> >>>> user-config.jam.
> >>>
> >>> I have updated the URL to:
> >>>
> >>> 	http://www.boost.org/boost-build2/doc/html/bbv2/overview/configuration.html
> >>>
> >>> where a table of locations of config files is present.
> >>
> >> Does not the search order for user-config.jam start with the boost build
> >> directory ?
> >
> > No. It starts with $HOME, because if it started with something else, user-config.jam
> > placed in $HOME would be ignored.
> >
> >> In the page above the search order for user-config.jam does
> >> not include that at all.
> >
> > That is the $BOOST_BUILD_PATH in the table.
> 
> So one of the environment variables must be set in order for 
> user-config.jam to be found and the user to be able to use the Boost 
> Build system ?

Not exactly. First, $HOME + $BOOST_BUILD_PATH applies for Unix. There,
$HOME is always set. Also, Boost.Build startup will append its own
location to BOOST_BUILD_PATH.

For Windows, the situation is similar, except that different variables
are used to find the user 'home directory'.

> I would imagine for a user downloading Boost and hoping to build some 
> part of Boost, having to set an environment variable in order to do so 
> might be an excessive requirement.

I think you probably have built freshly downloaded Boost a few times already,
without setting environment variables.

Thanks,

--
Vladimir Prus
http://vladimir_prus.blogspot.com
Boost.Build: http://boost.org/boost-build2