Platform Independent Path
You want to create a directory in a platform independent way. The directory is several levels deep and you wish to create intermediate directories as necessary.
Use the ensure_dir procedure in Erlang's filelib module.
1> filelib:ensure_dir("/what/a/great/test"). ok
Although the above directory tree looks like a POSIX file system, if this test is run on a Windows machine you will get the expected directory tree starting at the root of the current drive (usually C:). On a UNIX platform, you will get the expected directory tree.
As always your user permissions will limit what files and directories you are able to create or modify.