The default name for the root of a DCE cell's DFS filespace is fs, which is an entry in the cell's namespace. The fs entry, referred to as a junction, serves as a boundary between the CDS namespace and the DFS filespace. The contents of the fs junction provide the information necessary to access files and directories in the filespace.
The name fs is only a default; it is not considered to be well known and, thus, can vary from cell to cell. (See your vendor's installation and configuration documentation for information about specifying a name other than fs as the junction for a cell's DFS filespace.)
The name of a file or directory object in DFS includes the fs element in its path name to indicate that the object resides in the DFS filespace. Entries in the DFS filespace can be represented in DNS, GDS, and cell-relative format. The following examples are valid ways to refer to a directory in the abc.com cell, which uses DNS:
/.../abc.com/fs/usr/terry
/.:/fs/usr/terry
The following examples are valid ways to refer to a similar directory in the def.com cell, which uses GDS:
/.../C=US/O=def/OU=Writers/fs/usr/dale
/.:/fs/usr/dale
Entries in the DFS filespace also have a DFS-relative name that, like the cell-relative prefix, is usable only within the cell in which the entry exists. The DFS-relative name begins with the /: prefix, which is an abbreviation for both the global cell name and the fs entry that begins the DFS filespace. An example of a directory name represented in DFS-relative format follows; the name is valid only from within the local cell.
/:/usr/terry
Commands that use CDS interfaces know how to interpret the /: prefix. For example, the dcecp rpcentry command is able to interpret the /: prefix as /.../cellname/fs.
However, commands that access file and directory objects in the DFS filespace rely on the presence of a symbolic link to resolve the /: prefix. The symbolic link /: must reside in the root directory of the local machine, and it must point to the location of the DFS junction in the CDS namespace of the local cell. The link must be created on each DFS client machine; it is usually created when a machine is configured as a DFS client.
For example, suppose a path name that begins with the /: prefix is used with the dcecp acl command. For the command to succeed, the symbolic link /: must exist in the root directory of the machine on which the command is issued, and the link must point to the CDS entry /.../cellname/fs (or whatever name is used for the DFS junction in the local cell); otherwise, the command fails because it cannot interpret the /: prefix.
Note that the /.: and /: prefixes are abbreviations intended primarily for interactive use, not for use in persistent storage such as shell scripts. Use global names (of the form /.../cellname) for path names in persistent storage. Note especially that the /.: and /: prefixes cannot be used in strings in which a : (colon) has a reserved meaning. For example, you cannot use the prefixes in the definition of a PATH environment variable in operating systems such as UNIX; in this case, the : is used to separate different path names, so including a prefix in the definition of a PATH environment variable violates the reserved nature of the : for that variable.
Note: Examples and output in this part are displayed in DNS format. Use whatever format is appropriate for your cell (DNS or GDS); if it is enabled in your cell, a cell-relative prefix (/.:) or DFS-relative prefix (/:) can be substituted wherever a path begins with /.../abc.com or /.../abc.com/fs. Also, the term DCE path name refers to a name specified in any acceptable DCE Directory Service format. Finally, the examples in this part use the default, fs, as the junction of the DFS filespace.