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+--- Thread: Understanding the boot loader (/showthread.php?tid=2769)
Understanding the boot loader - balanga - 01-26-2024
I'm trying to figure out how the boot loader works, and it seems to me that it consists of two files boot.img and core.img.
Can someone confirm that that is the case?
RE: Understanding the boot loader - 0x6A7232 - 02-05-2024
(01-26-2024, 10:45 PM)balanga Wrote: I'm trying to figure out how the boot loader works, and it seems to me that it consists of two files boot.img and core.img.
Can someone confirm that that is the case?
Yes. Look in the Linux version VentoyWorker.sh in the tool folder (looks like Windows does all the work inside of the .exe so you can't see it there) and ctrl+F for core.img and boot.img
You can find where it puts boot.img into the mbr and core.img into the 1MB space at the beginning of the disk before the first partition.
RE: Understanding the boot loader - balanga - 02-17-2024
(02-05-2024, 09:36 PM)0x6A7232 Wrote:I know this but looking at the code in(01-26-2024, 10:45 PM)balanga Wrote: I'm trying to figure out how the boot loader works, and it seems to me that it consists of two files boot.img and core.img.
Can someone confirm that that is the case?
Yes. Look in the Linux version VentoyWorker.sh in the tool folder (looks like Windows does all the work inside of the .exe so you can't see it there) and ctrl+F for core.img and boot.img
You can find where it puts boot.img into the mbr and core.img into the 1MB space at the beginning of the disk before the first partition.
https://github.com/ventoy/Ventoy/blob/master/INSTALL/tool/VentoyWorker.sh
specifically lines 335+ :-
if [ -n "$VTGPT" ]; then
echo -en '\x22' | dd status=none of=$DISK conv=fsync bs=1 count=1 seek=92
xzcat ./boot/core.img.xz | dd status=none conv=fsync of=$DISK bs=512 count=2014 seek=34
echo -en '\x23' | dd of=$DISK conv=fsync bs=1 count=1 seek=17908 status=none
else
xzcat ./boot/core.img.xz | dd status=none conv=fsync of=$DISK bs=512 count=2047 seek=1
fiif [ -n "$VTGPT" ]; then
echo -en '\x22' | dd status=none of=$DISK conv=fsync bs=1 count=1 seek=92
xzcat ./boot/core.img.xz | dd status=none conv=fsync of=$DISK bs=512 count=2014 seek=34
echo -en '\x23' | dd of=$DISK conv=fsync bs=1 count=1 seek=17908 status=none
else
xzcat ./boot/core.img.xz | dd status=none conv=fsync of=$DISK bs=512 count=2047 seek=1
fi
I can't figure out what the lines '\x22' and '\x23' are supposed to do.
RE: Understanding the boot loader - nguyen ha thai trong - 03-05-2024
(01-26-2024, 10:45 PM)balanga Wrote: I'm trying to figure out how the boot loader works, and it seems to me that it consists of two files boot.img and core.img.You guessed it right
Can someone confirm that that is the case?