Previous code uses BasicOpenFile() + close().
access() should be faster than BasicOpenFile()+close() and access()
should be more correct since BasicOpenFile() could fail for various
cases (e.g. due to file permission, etc) even the file exists.
access() is supported on Linux/Unix. I do not have a Windows dev environment, but MSDN tells me that access() is supported on Windows also and there have been access() call in the workspace, so I assume there is no portability issue.
Thanks.