Of course, you can always specify an absolute path name for a file--for example:
env = Environment() env.Program('prog', ['main.c', '/usr/joe/lib/foo1.c', 'foo2.c'])
Which, when executed, would yield:
% scons -Q cc -o src/prog/foo2.o -c src/prog/foo2.c cc -o src/prog/main.o -c src/prog/main.c cc -o /usr/joe/lib/foo1.o -c /usr/joe/lib/foo1.c cc -o src/prog/prog src/prog/main.o /usr/joe/lib/foo1.o src/prog/foo2.o
(As was the case with top-relative path names, notice that the /usr/joe/lib/foo1.o object file is built in the same directory as its source file. See Chapter 17, below, for information about how to build the object file in a different subdirectory.)