In order to keep track of available volumes and files, OpenInsight maintains two system "files" -- SYSVOLUMES and SYSTABLES. As their names imply, these files contain information about currently available volumes and tables (files), respectively.
In fact, these files are simply system variables (@VOLUMES for data in SYSVOLUMES and @TABLES for data in SYSTABLES). However, to provide standard access to the information in these variables, they are accessible via the BFS RTP50 (memory resident files) as normal OpenInsight files. Because they are not true files, they cannot be updated by users.
Information in the SYSVOLUMES and SYSTABLES files is maintained by processes such as Attach_Table, Create_Table, Delete_Table, and others. For example, the Attach_Table process builds a SYSVOLUMES file entry for the volume being attached, and creates a series of SYSTABLES entries, one for each file being attached.
