On May 3 18:06, Eric Blake wrote: > The limitation here is not in dd, but in cygwin-1.5.16's use of the underlying > Window's features to access raw devices. Just because Linux has chosen > to allow a non-block access of a block-special device (implemented as a block > read, edit, block write sequence), it does not mean that Windows has to do > likewise. Perhaps cygwin 1.5.17 can be patched to do a read-write sequence > on block-special raw devices when write(2) is unaligned or not a full block, > at > which point dd would automatically work in the way you desire. And if you > really want that feature, consider patching cygwin yourself. Also, from your > original description, it sounds like write(2) was failing with ENOSPC when > Windows rejected the non-aligned write, although the better error to comply > with POSIX would have been ENXIO for a request outside of the device's > capabilities. I'd have to see an strace output to be sure (but right now I'm > not brave enough to risk overwriting my own MBR as an experiment to generate > such an strace output).
I like the read/write idea and I'd be happy to see a patch for this. If you want to debug this, why not just write to /dev/fd0? The floppy isn't handled any different in writing to raw devices. Corinna -- Corinna Vinschen Please, send mails regarding Cygwin to Cygwin Project Co-Leader mailto:cygwin@cygwin.com Red Hat, Inc. -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/