writing a sector from buffer to a bin file

[flyhigh427]

hey
im getting an error unable to open file.
and do i have to load into the buffer or just load straight into the file ?
thanks

Code: [Select]



TARGETDRIVE     equ       0             ; hard drive (0, 1, ...)


org 100h                               
Start:
        mov     dx,80h + TARGETDRIVE    ; read MBR of target drive
        mov     cx,1h                   ; it's always the first sector
        mov     bx, buffer       ; point to our buffer
        mov     ax, 0201h               ; read one sector
        int     13h
        mov     cx,4h                   ; read up to four entries
        mov     si, buffer + 1BEh; scan our partition table
        mov     si,begin
        mov ax, 4C00h                   ; Exit to DOS.
        int 21h

buffer db 0                            ;Dynamic buffer, 512 bytes.






Begin: INCBIN "holdsec.bin"


[Frank Kotler]

I'm not sure I understand the problem. "Begin" != "begin", but I don't think that's what you're talking about(?). You seem to be "incbin"ing a file, and then overwriting it. I don't "get" it.

Best,
Frank

[flyhigh427]

hey frank
i had caps on and fixed that.
im tryng to make a copy of my mbr

[Serge]

Hmmm...
flyhigh427, are you trying to write data to file "holdsec.bin"?
If yes, you are mistaken. INCBIN just places the content of file to the code at compilation time, not at execution.

[flyhigh427]

thanks

[Frank Kotler]

Right. Now I understand the question (Thanks, Serge!). Yeah, you'll have to read your MBR into a buffer (512 bytes +, please!), then open/create the file, and write the buffer to it. (or... you could write the buffer to stdout and redirect it - watch out for "helpful" dos routines that convert tabs to spaces, etc. - int 21h/40h should work)

Best,
Frank