Re: [Boost-users] Re: Are BOOST_BUILD_PATH && BOOST_ROOT necessary?

From: Steven T. Hatton (hattons_at_[hidden])
Date: 2004-09-05 22:19:29

On Saturday 04 September 2004 20:18, David Abrahams wrote:
> "Steven T. Hatton" <hattons_at_[hidden]> writes:
> > On Friday 03 September 2004 12:06, David Abrahams wrote:
> >> "Steven T. Hatton" <hattons_at_[hidden]> writes:

> The default within the Boost tree is v1.  The default elsewhere
> depends on where your boost-build.jam file points.
>

> > What are the "Boost.Build system files"?
>
> The contents of tools/build/v1 or tools/build/v2 depending on which
> version of Boost.Build you're using.
>

I could be mistaken, but I don't believe the documentation is clear on this 
point.

> > But that means everything is installed in the system's directory
> > structure.  That is not an ideal strategy for my purposes.  All
> > other libraries and tools I have are installed in my own user space.
>
> Your choice.  If it were me I'd keep the installed files out of the
> Boost source tree.

This is something I found confusing.  I typically download a tarball, extract 
it, and run 

./configure --prefix=$APPNAME_HOME && make && make install

That would be equivalent to what I expected from running 

bjam "-sTOOLS=gcc" install

When using the example above using ./configure, I can delete everything within 
the extracted image.  All I need in order to use the package would be placed 
in $APPNAME_HOME by make install.
 
> >> > Is there anything else I need to do in order to compile my programs
> >> > against the boost headers and libraries?
> >>
> >> Add the include/ directory to your #include path and the lib/
> >> directory to your library search path?
> >
> > By that am I to understand that when using the default installation
> > my CPLUS_INCLUDE_PATH
> >
> I don't know what that is.  I just meant add
> -I/usr/local/include/boost-1_31 to your compiler options.
>
The documentation does not explicitly state that CPLUS_INCLUDE_PATH is for 
C++, but I am left with no other conclusion than that as the intent.

http://gcc.gnu.org/onlinedocs/gcc-3.3.3/gcc/Environment-Variables.html#Environment%20Variables
# Begin quote
Some additional environments variables affect the behavior of the 
preprocessor. 

CPATH 
C_INCLUDE_PATH 
CPLUS_INCLUDE_PATH 
OBJC_INCLUDE_PATH 
Each variable's value is a list of directories separated by a special 
character, much like PATH, in which to look for header files. The special 
character, PATH_SEPARATOR, is target-dependent and determined at GCC build 
time. For Windows-based targets it is a semicolon, and for almost all other 
targets it is a colon. 

CPATH specifies a list of directories to be searched as if specified with -I, 
but after any paths given with -I options on the command line. This 
environment variable is used regardless of which language is being 
preprocessed. 

The remaining environment variables apply only when preprocessing the 
particular language indicated. Each specifies a list of directories to be 
searched as if specified with -isystem, but after any paths given with 
-isystem options on the command line. 

In all these variables, an empty element instructs the compiler to search its 
current working directory. Empty elements can appear at the beginning or end 
of a path. For instance, if the value of CPATH is :/special/include, that has 
the same effect as -I. -I/special/include. 
#End quote

> > should contain /usr/local/include/boost-1_31
> > and my LIBRARY_PATH, and LD_LIBRARY_PATH should contain
> > /usr/local/lib?
>
> You could do it that way.  Or you can refer to the installed libraries
> with absolute paths, or you can add -l/usr/local/include/boost-1_31 to
> your compiler options.  Specifically how you point your build tools at
> the Boost components is not for us to prescribe.

Does Boost.Build use these variables?  I noticed some output that showed the 
values of LD_LIBRARY_PATH.  My understanding is that this is for the loader 
to use at runtime.  The LIBRARY_PATH is intended to be used at compile time. 

-- 
Regards,
Steven