Mildred

This document serves as a technical handbook for MILDRED (Multiple Index Lookup, Deletion, Replacement and Entry: Disk), a set of PDP-12 subroutines designed to manipulate LAP6-DIAL/DIAL-MS indexes.

Key features of the document include:

• Overview and Environment: MILDRED is a set of serially reusable subroutines. It requires specific memory configurations and relies on the DIAL-MS I/O routines.
• Usage: Instructions are provided on how to load and integrate MILDRED into a user's program. It defines entry points for the primary routines: LOOKUP (20), ENTER (22), REPLACE (24), and DELETE (26).

• Routine Descriptions: The manual details the functionality and calling sequences for:

  • LOOKUP: Searches the index for a specific file name and type.
  • ENTER: Adds a new file to the index, provided there is no naming conflict.
  • REPLACE: Allows for the replacement of an existing file entry.
  • FCF: A background conflict-search routine that identifies available file space.
  • DELETE: Removes files from the index.

• Technical Details: The document includes flowcharts illustrating the logic of these routines, as well as a comprehensive assembly listing of the code, including symbol definitions and memory address references.