I'm trying to build an application I've downloaded which uses the SCONS "make replacement" and the Fast Light Tool Kit Gui.

The SConstruct code to detect the presence of fltk is:

guienv = Environment(CPPFLAGS = '')
guiconf = Configure(guienv)

if not guiconf.CheckLibWithHeader('lo', 'lo/lo.h','c'):
    print 'Did not find liblo for OSC, exiting!'
    Exit(1)

if not guiconf.CheckLibWithHeader('fltk', 'FL/Fl.H','c++'):
    print 'Did not find FLTK for the gui, exiting!'
    Exit(1)

Unfortunately, on my (Gentoo Linux) system, and many others (Linux distributions) this can be quite troublesome if the package manager allows the simultaneous install of FLTK-1 and FLTK-2.

Being Idealistic, I attempted to modify the SConstruct file to use fltk-config --cflags and fltk-config --ldflags (or fltk-config --libs might be better than ldflags) by adding them like so:

guienv.Append(CPPPATH = os.popen('fltk-config --cflags').read())
guienv.Append(LIBPATH = os.popen('fltk-config --ldflags').read())

But this causes the test for liblo to fail! Looking in config.log shows how it failed:

scons: Configure: Checking for C library lo...
gcc -o .sconf_temp/conftest_4.o -c "-I/usr/include/fltk-1.1 -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_THREAD_SAFE -D_REENTRANT"
gcc: no input files
scons: Configure: no

How should this really be done?