ORG替代的C ++ [英] ORG alternative for C++

问题描述

在组装使用组织指令将位置计数器设置在内存中的特定位置。这是在使操作系统特别有用。下面是一个例子引导加载程序（从维基）：

In assembly we use the org instruction to set the location counter to a specific location in the memory. This is particularly helpful in making Operating Systems. Here's an example boot loader (From wikibooks):

 org 7C00h

         jmp short Start ;Jump over the data (the 'short' keyword makes the jmp instruction smaller)

 Msg:    db "Hello World! "
 EndMsg:

 Start:  mov bx, 000Fh   ;Page 0, colour attribute 15 (white) for the int 10 calls below
         mov cx, 1       ;We will want to write 1 character
         xor dx, dx      ;Start at top left corner
         mov ds, dx      ;Ensure ds = 0 (to let us load the message)
         cld             ;Ensure direction flag is cleared (for LODSB)

 Print:  mov si, Msg     ;Loads the address of the first byte of the message, 7C02h in this case

                         ;PC BIOS Interrupt 10 Subfunction 2 - Set cursor position
                         ;AH = 2
 Char:   mov ah, 2       ;BH = page, DH = row, DL = column
         int 10h
         lodsb           ;Load a byte of the message into AL.
                         ;Remember that DS is 0 and SI holds the
                         ;offset of one of the bytes of the message.

                         ;PC BIOS Interrupt 10 Subfunction 9 - Write character and colour
                         ;AH = 9
         mov ah, 9       ;BH = page, AL = character, BL = attribute, CX = character count
         int 10h

         inc dl          ;Advance cursor

         cmp dl, 80      ;Wrap around edge of screen if necessary
         jne Skip
         xor dl, dl
         inc dh

         cmp dh, 25      ;Wrap around bottom of screen if necessary
         jne Skip
         xor dh, dh

 Skip:   cmp si, EndMsg  ;If we're not at end of message,
         jne Char        ;continue loading characters
         jmp Print       ;otherwise restart from the beginning of the message


 times 0200h - 2 - ($ - $$)  db 0    ;Zerofill up to 510 bytes

         dw 0AA55h       ;Boot Sector signature

 ;OPTIONAL:
 ;To zerofill up to the size of a standard 1.44MB, 3.5" floppy disk
 ;times 1474560 - ($ - $$) db 0

是否有可能实现与C ++的任务吗？是否有任何命令，函数等，如组织在那里我可以改变程序的位置？

Is it possible accomplish the task with C++? Is there any command, function etc. like org where i can change the location of the program?

推荐答案

没有它不可能在任何C编译器，我知道的事情。但是，您可以创建放置code你自己的链接脚本 /数据/ BSS段在特定的地址。

No it's not possible to do in any C compiler that I know of. You can however create your own linker script that places the code/data/bss segments at specific addresses.

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