Dir()

The File and Dir functions return File and Dir Nodes (as python objects), respectively. Those objects have several user-visible attributes and methods that are often useful:

• path - The build path of the given file or directory. This path is relative to the top-level directory (where the SConstruct file is found). The build path is the same as the source path if build_dir is not being used.
• abspath - The absolute build path of the given file or directory.
• srcnode() - returns another File or Dir object representing the source path of the given File or Dir. See also File().

# Get the current build dir's path, relative to top.
Dir('.').path
# Current dir's absolute path
Dir('.').abspath
# Next line is always '.', because it is the top dir's path relative to itself.
Dir('#.').path
File('foo.c').srcnode().path   # source path of the given source file.

# Builders also return File objects:
foo = env.Program('foo.c')
print "foo will be built in %s"%foo.path