If you allocate the same library via different pathnames, SAS cannot keep track of existing locks on the datasets in the library. If a conflict occurs, the following error message might appear:
ERROR: A lock is not available for <libref>.<member>.DATA, lock held by another process.
The ability to point to the same location via different pathnames differs under each system. An example of how this can occur under Windows is as follows:
libname lib1 '\\server\Public\SAS Library'; libname lib2 'G:\SAS Library';
The pathname for LIB1 uses a UNC pathname, and the pathname for LIB2 uses a drive that is mapped to the same Public share on the same server. Windows allows other ways of pointing to the same location also. For example, Microsoft Distributed File System allows the use of one tree "path" to represent a collection of multiple UNC paths. A similar situation could exist on UNIX: for example, if a pathname to the same location is constructed via different but compatible file systems, such Andrew File System (AFS) and Network File System (NFS).