.sect .text; .sect .rom; .sect .data; .sect .bss; .sect .text .define __sbrk .extern __sbrk, xbrk, cerror __sbrk: push bp mov bp,sp mov ax,4(bp) mov bx,(np) add ax,bx mov cx,sp sub cx,128 sub cx,ax jbe 1f mov (np),ax sub ax,bx jbe 2f call xbrk 2: mov ax,bx pop bp ret 1: mov ax,0xc pop bp jmp cerror