Format of kernel entry jump table for DR DOS 5.0-6.0

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Offset	Size	Description
00h	5 BYTEs	far jump to kernel entry point for CP/M CALL 5
05h	5 BYTEs	far jump to kernel entry point for INT 20
0Ah	5 BYTEs	far jump to kernel entry point for INT 21
0Fh	5 BYTEs	far jump to kernel entry point for INT 22 (RETF)
14h	5 BYTEs	far jump to kernel entry point for INT 23 (RETF)
19h	5 BYTEs	far jump to kernel entry point for INT 24
1Eh	5 BYTEs	far jump to kernel entry point for INT 25
23h	5 BYTEs	far jump to kernel entry point for INT 26
28h	5 BYTEs	far jump to kernel entry point for INT 27
2Dh	5 BYTEs	far jump to kernel entry point for INT 28
32h	5 BYTEs	far jump to kernel entry point for INT 2A (IRET)
37h	5 BYTEs	far jump to kernel entry point for INT 2B (IRET)
3Ch	5 BYTEs	far jump to kernel entry point for INT 2C (IRET)
41h	5 BYTEs	far jump to kernel entry point for INT 2D (IRET)
46h	5 BYTEs	far jump to kernel entry point for INT 2E (IRET)
4Bh	5 BYTEs	far jump to kernel entry point for INT 2F

Note:

All of these entry points are indirected through this jump table to allow the kernel to be relocated into high memory while leaving the actual entry addresses in low memory for maximum compatibility.
Some of these entry points (22h,23h,24h,2Eh,2Fh) are replaced as soon as COMMAND.COM is loaded, and return immediately to the caller, some returning an error code (the original handler for INT 2F returns AL=03h [fail]).