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shamurshamur
As we all know , by default isolinux.bin look for a file name isolinux.cfg in some pre-defined path like "/isolinux" " /boot/isolinux/" etc .

My question is there any way ( like hex editing of isolinux.bin ) , that we can make isolinux.bin look for different .cfg file other then the " isolinux.cfg " and in some different path other then the pre-defined default paths.
jaclaz
You can try mixing together the info from these two:
http://syslinux.zytor.com/archives/2005-December/006364.html
http://www.ezbsystems.com/cgi-bin/ikonboar...=1687;&#top

and shake well wink.gif, but I am not sure isolinux hasn't a checksum that prevents the above. unsure.gif

jaclaz
shamurshamur
QUOTE (jaclaz @ Apr 18 2009, 08:45 PM) *
You can try mixing together the info from these two:
http://syslinux.zytor.com/archives/2005-December/006364.html
http://www.ezbsystems.com/cgi-bin/ikonboar...=1687;&#top

and shake well wink.gif, but I am not sure isolinux hasn't a checksum that prevents the above. unsure.gif

jaclaz


yes , checksum error is the main problem with isolinux.bin. Not only that , it some times give " checksum error " when iso file is not formed with proper options, even if isolinux.bin has not been modified.

Can somebody tell me , how the mechanism of this checksum ( in isolinux.bin ) actually works?
Is there any method by which we can disable this checksum error in isolinux.bin.??
cdob
QUOTE (shamurshamur @ Apr 18 2009, 01:26 PM) *
My question is there any way ( like hex editing of isolinux.bin ) , that we can make isolinux.bin look for different .cfg file

Yes, hexediting is possible: e.g. change isolinux.cfg to isolinux.cf2


QUOTE (shamurshamur @ Apr 18 2009, 05:14 PM) *
checksum error is the main problem with isolinux.bin.

Use a current isolinux version.

And use the author recommended solution: adjust isolinux.bin boot-info-table
http://syslinux.zytor.com/wiki/index.php/ISOLINUX
QUOTE
mkisofs ... -boot-info-table
shamurshamur
QUOTE (cdob @ Apr 18 2009, 11:02 PM) *
Yes, hexediting is possible: e.g. change isolinux.cfg to isolinux.cf2



Use a current isolinux version.

And use the author recommended solution: adjust isolinux.bin boot-info-table
http://syslinux.zytor.com/wiki/index.php/ISOLINUX

Well,thanks cdob!
i tried changing the name of "isolinux.cfg" to "isolinux.cf2"

1) it worked when i used the isolinux.bin as bootsector of the iso .
2) it didn't worked ( again checksum error ) , when i used the loader.bin ( bootsector for loading bcdw.bin ) as bootsector of iso.and then called the isolinux.bin from bcdw.ini.


i still want to know any method to totally disable this " checksum error " by isolinux.bin . ( ie isolinux.bin should not execute this "checksum" maneuver )
Also , are both the options "-boot-load-size " and "-boot-info-table" compatible?? and what's the purpose of using " -boot-load-size " option.
FM_81
for info: there exists some variables inside ISOLINUX.BIN
0xc => startsector of ISOLINUX.BIN itself
0x10 => size of ISOLINUX.BIN in bytes
0x14 => the checksum

all these will modified automatically if you use MKISOFS for building and the parameter "-boot-info-table"
"-boot-load-size" I have always set to "4"

Some years ago I've been using a patched variant myself, this has never caused problems ...

EDIT: you need no additional bootsector, ISOLINUX.BIN itself is the bootsector!

EDIT 2: As far as I remember exists an isolinux-module for BCDW, which works without these kind of "selfmodification"

MfG, FM_81
shamurshamur
QUOTE (FM_81 @ Apr 19 2009, 12:15 AM) *
for info: there exists some variables inside ISOLINUX.BIN
0xc => startsector of ISOLINUX.BIN itself
0x10 => size of ISOLINUX.BIN in bytes
0x14 => the checksum

all these will modified automatically if you use MKISOFS for building and the parameter "-boot-info-table"
"-boot-load-size" I have always set to "4"

Some years ago I've been using a patched variant myself, this has never caused problems ...

EDIT: you need no additional bootsector, ISOLINUX.BIN itself is the bootsector!

EDIT 2: As far as I remember exists an isolinux-module for BCDW, which works without these kind of "selfmodification"

MfG, FM_81

Thanks FM_81,
where can i find this "isolinux-module " for bcdw.

Can you tell me how to hexedit any isolinux.bin file to stop it from checking the checksum , therefore avoiding the "checksum error"
cdob
QUOTE (shamurshamur @ Apr 18 2009, 09:09 PM) *
where can i find this "isolinux-module " for bcdw.

There is no "isolinux-module" for bcdw.

BCDW calls isolinux, add options yourself: http://bootcd.narod.ru/bcdw_e.htm#isolinux
FM_81
QUOTE (cdob @ Apr 18 2009, 10:34 PM) *
There is no "isolinux-module" for bcdw.
You're right, my mismatch!
CD-Shell has or had one; long time ago I've used BCDW or CD-Shell ... whistling.gif

MfG, FM_81
FM_81
QUOTE (shamurshamur @ Apr 18 2009, 10:09 PM) *
Can you tell me how to hexedit any isolinux.bin file to stop it from checking the checksum , therefore avoiding the "checksum error"
I see no chance for this, because MKISOFS does this modification during build. An the changes in ISOLINUX.BIN depends on it's position inside the ISO-file (which we're building in the same moment) ...

But you can use -eltorito-alt-boot option and create a second boot-image.
I know no BIOS, which sees this, but this is not the important part.
The modification with -boot-info-table is also allowed too for this second. An (incomplete!) example:
CODE
mkisofs.exe <...filesystem_options...> -b bcdw/loader.bin -no-emul-boot -boot-load-size 4 -eltorito-alt-boot -b boot/isolinux/isolinux.bin -no-emul-boot -boot-load-size 4 -boot-info-table <...output_file...source_dir...>
(all in one line)bcdw/loader.bin is here the primary, boot/isolinux/isolinux.bin the second and it, gets the modification. Paths are relative to your given CD-root.

MfG, FM_81
Jotnar
@shamurshamur

Are you trying to use BCDW as your main menu or are you just trying to get back to ISOLinux?

For those interested in the first part of the what shamurshamur is trying to do: http://ubcd4win.com/forum/index.php?showtopic=12790

Cheers
jaclaz
@jotnar

Nice thread. smile.gif

Just as a FYI, newish grub4dos has gfxmenu compatibility back.

And there is still Aerostudio if you really want to "get graphical".

Posted a couple examples here:
http://www.msfn.org/board/index.php?showto...129399&st=5

jaclaz
jaclaz
Just for the record, unrelated, but not much wink.gif:
http://www.boot-land.net/forums/index.php?showtopic=8258
http://www.boot-land.net/forums/index.php?...=8258&st=31

QUOTE (Icecube)
@ jaclaz
Maybe you can add a link to http://www.boot-land.net/forums/index.php?showtopic=9582 on the topic that you linked too.
The patch for chain.c32 is in Syslinux 3.83. It is not directly related to BCDW, but might still be useful.


jaclaz
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