lynx port

[Ryan Schmidt]

On Mar 30, 2007, at 21:22, Vincent Lefevre wrote:

> On 2007-03-30 09:10:35 -0400, Daniel J. Luke wrote:
>
>>  The macports change to always add -I and -L options isn't in a  
>> release
>>  version (yet). We should probably think about it some more and do  
>> lots of
>>  testing to make sure that it won't break many (any?) ports.
>
> That's a reason why I think that using the CPATH / LIBRARY_PATH
> environment variables instead of adding -I and -L options would
> be a better solution.

Trying to find more info, I found this document:

http://www.network-theory.co.uk/docs/gccintro/gccintro_23.html

which describes LIBRARY_PATH, C_INCLUDE_PATH and CPLUS_INCLUDE_PATH.  
I can't find a document describing CPATH. I have never heard of any  
of these four variables before.

Can someone explain the relationships between LIBRARY_PATH,  
C_INCLUDE_PATH, CPLUS_INCLUDE_PATH, CPATH, CFLAGS, CPPFLAGS,  
CXXFLAGS, LDFLAGS, possibly LD_LIBRARY_PATH and DYLD_LIBRARY_PATH,  
and any other similar variables I may not yet know about, and give  
advice about the scenarios in which one might want to use each of  
them, or point to a document where such explanations are already  
made? With so many variables it's becoming very difficult to  
understand how mere mortals are meant to be able to compile anything  
at all.

In particular if C_INCLUDE_PATH and CPLUS_INCLUDE_PATH (or possibly  
CPATH) and LIBRARY_PATH are to be preferred instead of CFLAGS,  
CPPFLAGS, CXXFLAGS and LDFLAGS, I'm a little surprised I've never  
heard of this before.