HelpPC 2.10 Quick Reference Utility Copyright 1991 David Jurgens

            DOS Undocumented Interrupts, Functions and Structures

       INT 15,20   PRINT.COM Critical Region Flag (DOS 3.x+)
       INT 21,1F   Get pointer to current drive parameter table
       INT 21,32   Get pointer to drive parameter table
       INT 21,34   Get address to DOS critical flag (INDOS flag)
       INT 21,37   Get/set switch char
       INT 21,4B   EXEC/Load and execute (Function 1 undocumented)
       INT 21,50   Set current process id (DOS 2.x)
       INT 21,51   Get current process id (DOS 2.x)
       INT 21,52   Get pointer to DOS "INVARS"
       INT 21,53   Generate drive parameter table
       INT 21,55   Create new PSP
       INT 21,58   Get/set memory allocation strategy (DOS 3.x+)
       INT 21,5D   Critical error information (DOS 3.x+)
       INT 21,60   Get fully qualified file name (DOS 3.x+)
       INT 21,64   Set device driver look ahead  (DOS 3.3+)
       INT 21,69   Get/set disk serial number (DOS 4.0+)
       INT 21,F8   Set INT 21 OEM handler
       INT 28      DOS idle loop/scheduler
       INT 29      Fast character output
       INT 2E      Execute command using base level COMMAND.COM

       BCB         Batch Control Block
       DTA         Disk Transfer Area  (partially undocumented)
       MCB         Memory Control Block
       PSP         Program Segment Prefix Layout (partially undocumented)
       SFT         System File Table

       - the above items are undocumented with respect to IBM/Microsoft
         and should be not be used unless one fully understands the
       - several functions are version dependant and OEM specific

Esc or Alt-X to exit undocumented Home/PgUp/PgDn/End ←↑↓→
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