On Wed, 2009-04-15 at 15:46 +0200, Niki Kovacs wrote: > Michael A. Peters a écrit : > > >> > >> 1) Am I supposed to be root to use cdrecord and burn an .iso file? > > > > I've found it works much better if you are root. > > > > I tried both, and see: cdrecord complains about not being able to set > certain priorities while being run as user, which induces a high risk > for buffer underruns. So I have my answer for that. > > Another cdrecord-related question. Usually I should be able to copy a CD > as simply as that: > > $ dd if=/dev/cdrom of=copy.iso > > Then insert a blank CD, and: > > $ cdrecord -v -eject dev=/dev/cdrom copy.iso > > Now I did that for data CDs, and it works very well. I thought, normally > this *should* also work for audio CDs, so I gave that a spin. But > everytime I try it, dd stops short and gives me an "Input/output error" > for /dev/hdc. > > I tried three different audio CDs, all three in good state. I can listen > to them OK on the PC. But all I get with dd is a zero-byte-length > copy.iso file. > > Any idea what's happening? Try padding copied image with a few hundred k of nulls. dd if=/dev/zero of=copy.iso \ seek=<number of output blocks to skip forward> bs=2048 I've had to do this for my ISO images depending on the age/brand/model of the device. It seems that (at least in the past) there was a disconnect in the kernel handling of the end of file and writing the last blocks read in. This cured it. I can't say if this would affect audio CDs as well, but worth a try. > > Niki > <snip sig stuff> HTH -- Bill