Tested powerpc64le-linux, x86_64-dragonfly4.1 and x86_64-netbsd5.1, do you see any reason not to commit this for now?
I see only a couple of potential problems: a missing test for PATH_MAX in the unlikely event it's not defined (or is obscenely large), and a missing check to avoid infinite loops due to symlinks.
Any improvements such as hardcoding checks for specific versions of Solaris or the BSDs are QoI, and this is only an experimental TS, so I don't want to spend the rest of stage 1 working on one function :-)
Makes sense.
My main obstacle to writing good tests right now is having some way to create and destroy files safely in the tests. It's hard to test functions like is_symlink() without first creating a symlink in a known location, and also removing it again cleanly so the next testsuite run doesn't fail if the file is already present. One option would be to have libstdc++-v3/testsuite/Makefile create a new sub-directory as a sandbox for filesystem tests, removing it if it already exists. Then the tests can put anything they like in that new dir without fear of trashing the user's files elsewhere on the FS!
I don't know how you feel about Tcl but writing a filesystem.exp and adding a new "dg-fs" API would let each test can set up the directory structure it needs. Martin