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.387
.386p
name prt0
assume nothing
extrn PASCALMAIN : near
extrn HEAPSIZE : dword
public start
public ___exit
public ___sbrk
public HEAP
public PSP_SELECTOR
public ENV_SELECTOR
public ENV_SIZE
.STACK 1000h
.CODE
start proc near
jmp short main
db "WATCOM"
main:
mov ax,es ; psp selector in es
mov PSP_SELECTOR,ax
mov gs,ax
mov bx,[gs:2Ch] ; environment sel. at psp_sel:2C
mov ENV_SELECTOR,bx
lsl ecx,bx ; get selector limit
mov ENV_SIZE,ecx
push ds
pop es
push ds
pop fs
mov eax,HEAPSIZE
push eax
call ___sbrk ; allocate heap
mov HEAP,eax
pop eax
call PASCALMAIN
start endp
___exit proc near
pop eax
mov ah,4Ch
int 21h
___exit endp
___sbrk proc near
mov ebx,dword ptr [esp+4]
mov ecx,ebx
shr ebx,16
mov ax,501h
int 31h
jnc sbrk_ok
xor eax,eax
ret
sbrk_ok:
shl ebx,16
mov bx,cx
mov eax,ebx
ret
___sbrk endp
.DATA
HEAP dd 0
PSP_SELECTOR dw 0
ENV_SELECTOR dw 0
ENV_SIZE dd 0
end start
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