en:docs:dos:api:int21:00

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Note: This API call is for DOS and Win16 personality only. Use Family API for portability.

2018/09/07 05:04 · prokushev · 0 Comments

Int 21H, AH=00H

Version

1 and higher

Brief

TERMINATE PROGRAM

Family API

Input

AH = 00h
CS = PSP segment

Return

never returns

Notes

Microsoft recommends using INT 21/AH=4Ch for DOS 2+. This function sets the program's return code (ERRORLEVEL) to 00h. Execution continues at the address stored in INT 22 after DOS performs whatever cleanup it needs to do (restoring the INT 22,INT 23,INT 24 vectors from the PSP assumed to be located at offset 0000h in the segment indicated by the stack copy of CS, etc.). If the PSP is its own parent, the process's memory is not freed; if INT 22 additionally points into the terminating program, the process is effectively NOT terminated. Not supported by MS Windows 3.0 DOSX.EXE DOS extender

See also

AH=4Ch,AH=26h,AH=31h, INT 20

Note

2018/09/04 17:23 · prokushev · 0 Comments