Each file access by DMS is preceded by an access to the catalog entry for the file to be processed. When specifying a file name in a macro or command, the user can generally use various combinations of the catalog ID, user ID and file name. Temporary files are normally addressed with the prefix and file name only (the default catalog ID and/or default user ID may be specified).
pathname = [:catid:][$userid.]filename
filename
DMS searches for the file in the catalog belonging to the user ID of the job issuing the request. If this is unsuccessful, the function “secondary read” is performed for several commands (or if the operand OPTION=GLODEF is specified in the FCB macro; see next section). Otherwise, DMS issues an appropriate error message.
$userid.filename
DMS searches for the file in the default catalog assigned to the specified user ID. If the user ID of the job issuing the request is neither the owner nor the co-owner of the file nor TSOS, the file must be shareable. If the file is not found, DMS issues the appropriate error messages.
:catid:$userid.filename
DMS searches for the file in the specified catalog under the specified user ID. If no entry for the file is found there, DMS issues the appropriate error message.
:catid:filename
DMS searches for the file in the named catalog under the user ID of the job which issues the request. Assumed, of course, that there is a corresponding entry in the user catalog for the user ID in the named catalog. A secondary read is possible (see next section). If the access attempt is unsuccessful, DMS issues an appropriate error message.
The catalog entry indicates how and where the file is stored (volume list and position information).