How2 'dd' bootable-CD's bloks ?
in [Linux Hardware]
|
From: no.top.post on 24 Jan 2010 01:26 There's a [non-linux / non-M$] app. which I can boot from fd0, and which I previously tweeked by editing some of the initial bytes on the fd0 -- I think linux's rdev is similar. Now I've got the newer CD-based version, and it doesn't show on my PC, but it runs on newer PCs. So I'm guessing that the video args are wrong for me. Read > Edit > Write the CD could be difficult, but I'd like to at least see the first few block's of bytes. ------> I tried:---- --> dd count=64 if=/mnt/cdrom/ETH of=/home/Debug/DVDw/AosCDhead == dd: reading `/mnt/cdrom/ETH': Is a directory 0+0 records in 0+0 records out ---- Where actually /mnt/cdrom/ETH is the original CD copied to a DVD, together with an ext2-CD. In order to check if my box can read DVD+R, I got someone with a M$-box to copy 2 CD-R to a test DVD+R. My PC can read the DVD+R, except that the MS-box wrote all fileNames 8+3-format. Sorry for 'life is complex' story. I also can't "dd" the original bootable CD-R . ----> and then 'apropos' got me to:---- man -> isoinfo [ -d ] [ -h ] [ -R ] [ -J ] [ -j charset ] [ -f ] [ -l ] [ -p ] [ -T sector ] [ -N sector ] [ -i isoimage ] [ -x path ] -i filename Filename to read ISO-9660 image from --> # isoinfo -i /mnt/cdrom == CD-ROM is NOT in ISO 9660 format ----------- Is it realistic to expect to be able to see the initial byte-sequence, like you can see a /dev/hdx or /dev/fdx Master-Boot-Record? == TIA.
From: Greg Russell on 24 Jan 2010 01:40 <no.top.post(a)gmail.com> wrote in message news:hjgp6e$jcl$1(a)news.eternal-september.org... .... > Read > Edit > Write the CD could be difficult, but I'd like to > at least see the first few block's of bytes. > ------> I tried:---- > --> dd count=64 if=/mnt/cdrom/ETH of=/home/Debug/DVDw/AosCDhead > == dd: reading `/mnt/cdrom/ETH': Is a directory > 0+0 records in > 0+0 records out .... > I also can't "dd" the original bootable CD-R . One "dd"s a device, not a filesystem, e.g.: $ ls -l /dev/cdrom lrwxrwxrwx 1 root root 3 Jan 11 09:09 /dev/cdrom -> hdc $ dd count=64 if=/dev/hdc of=/home/Debug/DVDw/AosCDhead
From: Grant on 24 Jan 2010 02:39 On Sat, 23 Jan 2010 22:40:36 -0800, "Greg Russell" <grussell(a)invalid.org> wrote: ><no.top.post(a)gmail.com> wrote in message >news:hjgp6e$jcl$1(a)news.eternal-september.org... > >... >> Read > Edit > Write the CD could be difficult, but I'd like to >> at least see the first few block's of bytes. >> ------> I tried:---- >> --> dd count=64 if=/mnt/cdrom/ETH of=/home/Debug/DVDw/AosCDhead >> == dd: reading `/mnt/cdrom/ETH': Is a directory >> 0+0 records in >> 0+0 records out >... >> I also can't "dd" the original bootable CD-R . > >One "dd"s a device, not a filesystem, e.g.: ITYM: dd's a file, not a directory? > >$ ls -l /dev/cdrom >lrwxrwxrwx 1 root root 3 Jan 11 09:09 /dev/cdrom -> hdc > >$ dd count=64 if=/dev/hdc of=/home/Debug/DVDw/AosCDhead > > Grant. -- http://bugs.id.au
From: Tauno Voipio on 24 Jan 2010 04:39 no.top.post(a)gmail.com wrote: > There's a [non-linux / non-M$] app. which I can boot from fd0, > and which I previously tweeked by editing some of the initial > bytes on the fd0 -- I think linux's rdev is similar. > > Now I've got the newer CD-based version, and it doesn't show on my > PC, but it runs on newer PCs. So I'm guessing that the video args > are wrong for me. > > Read > Edit > Write the CD could be difficult, but I'd like to > at least see the first few block's of bytes. > ------> I tried:---- > --> dd count=64 if=/mnt/cdrom/ETH of=/home/Debug/DVDw/AosCDhead > == dd: reading `/mnt/cdrom/ETH': Is a directory > 0+0 records in > 0+0 records out > ---- > Where actually /mnt/cdrom/ETH is the original CD copied to a DVD, > together with an ext2-CD. In order to check if my box can read DVD+R, > I got someone with a M$-box to copy 2 CD-R to a test DVD+R. > My PC can read the DVD+R, except that the MS-box wrote all fileNames > 8+3-format. Sorry for 'life is complex' story. > > I also can't "dd" the original bootable CD-R . > > ----> and then 'apropos' got me to:---- > man -> isoinfo [ -d ] [ -h ] [ -R ] [ -J ] [ -j charset ] [ -f ] [ -l ] > [ -p ] [ -T sector ] [ -N sector ] [ -i isoimage ] [ -x path ] > > -i filename Filename to read ISO-9660 image from > > --> # isoinfo -i /mnt/cdrom == CD-ROM is NOT in ISO 9660 format > ----------- > > Is it realistic to expect to be able to see the initial byte-sequence, > like you can see a /dev/hdx or /dev/fdx Master-Boot-Record? > > == TIA. The CD boot information is outside of the file area, so it will not be visible on a mounted ISO9660 file system. For details, Google for 'El Torito specification'. -- Tauno Voipio
|
Pages: 1 Prev: Relatively inexpensive video cards for Linux Next: ECC error correction/scrubbing on x86-64 |