Table of Contents
Note: This API call is for DOS personality only. Use Family API for portability.
Int 21H, AH=51H
Version
2 and higher
Brief
GET CURRENT PROCESS ID (GET PSP ADDRESS)
Family API
Input
AH = 51h
Return
BX = segment of PSP for current process
Notes
DOS uses the current PSP address to determine which processes own files
and memory; it corresponds to process identifiers used by other OSs
under DOS 2.x, this function cannot be invoked inside an INT 28h
handler without setting the Critical Error flag
under DOS 3.0+, this function does not use any of the DOS-internal
stacks and may thus be called at any time, even during another
INT 21h call
supported by OS/2 compatibility box
identical to the documented AH=62h
this call was undocumented prior to the release of DOS 5.0
See also
AH=26h,AH=50h,AH=62h
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 |
