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Table of Contents
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
Text based on Ralf Brown Interrupt List Release 61
| osFree Macro Library | |
|---|---|
| Video I/O | @SetMode @SetCurSz @SetCurPos @GetCur @SetPage @ScrollUp @ScrollDn @Scroll @GetChAtr @PutChAtr @PutCh @SetPalet @SetColor @SetDot @GetDot @WrtTTY @VideoState @GetMode @GetDisplay @GetVideoState @GetEGAInfo @Cls |
| Hardware info | @Equipment @MemSize |
| Serial I/O | @AuxInit @AuxSendChar @AuxRecieveChar @AuxStatus |
| Tape I/O | @TapeOn @TapeOff @TapeRead @TapeWrite |
| Keyboard I/O | @KbdStatus @CharIn @CharPeek |
| Printer I/O | @PrnPrint @PrnInit @PrnStatus |
| Disk I/O | @DskReset @DskStatus @DskRead @DskWrite @DskVerify @DskFormat |
| Date and Time | @SetTime @GetTime |
| Mouse | @MouInit @MouShowPointer @MouStatus @MouSetPos @MouSetMickey @MouRegion |
| Memory manager | @ModBlok SET_BLOCK |