A series of MFS calls -- examples include CREATE.MEDIA, OPEN.MEDIA, and WRITE.MEDIA -- provide MFS programmers with access to media-related file functions. Media calls are defined as those that access the media map for a volume when executing.
Media Map Access
From the BASIC+ or the System Monitor, a media map is accessible via the logical file name REVMEDIA. This name is used for all media maps, regardless of volume or filing structure.
To access the media map, a user attaches the logical file name REVMEDIA for the volume being accessed. For example, to attach the media map for the default (DATAVOL) volume, execute this System Monitor command:
RUN ATTACH_TABLE "DATAVOL", "REVMEDIA"
The output from a successful ATTACH_TABLE is shown below:
From this point, the media map can be accessed using any file or record-oriented command. For example, rows in the REVMEDIA table can be edited using the System Editor, as shown below:
