gistfile1.txt

[jbeda@web:/tmp/foo]$ mkdir -p reala/a
[jbeda@web:/tmp/foo]$ mkdir -p realb/b
[jbeda@web:/tmp/foo]$ mkdir virtual
[jbeda@web:/tmp/foo]$ ln -s v^Ctual ../
[jbeda@web:/tmp/foo]$ cd virtual/
[jbeda@web:/tmp/foo/virtual]$ ln -s ../reala/a a
[jbeda@web:/tmp/foo/virtual]$ ln -s ../realb/b b
[jbeda@web:/tmp/foo/virtual]$ cd a
[jbeda@web:/tmp/foo/virtual/a]$ pwd
/tmp/foo/virtual/a
[jbeda@web:/tmp/foo/virtual/a]$ cd ../b
[jbeda@web:/tmp/foo/virtual/b]$ pwd
/tmp/foo/virtual/b