Re: How to react on a factually wrong Debian wiki change ?
Hi,
Brian proposed:
> There is (strong? extensive?) evidence that wodim should not be used
> with DVD or BD media. However, the many variables involved, especially
> burner types and media type and quality, could result a successful
> burn.
There are not that many variables:
Drive type: burner/reader of CD, DVD, BD media.
Medium type: DVD-R, DVD-R DL, DVD+R, DVD+R DL DVD+RW, DVD-RW, DVD-RAM,
BD-R, BD-RE (other than with DVD, the multi-layer BD media
do not differ in behavior from the single-layer BD media)
Medium write state: blank, appendable, closed.
Medium formatting state: DVD-RW and BD-R have more than one personality.
A burn program should know them and be able to handle their possible
combinations. That's what wodim fails to do with DVD and BD.
Erratic variables are the health of computer, drive, and medium.
(Error key B often indicates power supply or bus problems.
OPC errors or write errors often indicate problems of the drive and/or
of the medium.)
Richard Hector proposed:
> "wodim may sometimes work with DVD or BD media, but the results will not
> meet the relevant specifications."
It is not so much about the results. If the drive is healthy and does not
barf on wodim's commands, then a healthy medium gets written readable data.
It is about wodim's cluelessness about DVD and the lack of maintainership.
Be it about error replies from the drive
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=609763
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=651847
(Did not recognize Descriptor format sense code. The reported error is
B,0,0 (= abort message, actually from kernel) not 0,0,3 (=nonsense).)
Be it about single-session DVD+R
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=386640
Be it about multi-session on DVD+R
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=641147
Be it about double-layer features
https://bugs.launchpad.net/linuxmint/+bug/1094796
Be it about media types more modern than wodim's last change
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=782429
Not to forget the wonderful bit rot (not DVD specific)
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=679839
(One would just have to let it scan /dev/sr* rather than /dev/scd*.)
Who advises wodim for DVD or BD should also care for these bug reports.
----------------------------------------------------------------------
The Debian BurnCd wiki page shall give tangible instructions for users,
not discuss under what circumstances inappropriate SCSI preparations
succeed nevertheless.
Given the history, the bug reports, and the maintainership situation,
i still stand by the straight statement:
wodim should better not be used with DVD or BD media.
The word "better" indicates that success with wodim is not impossible.
(I just tested. DVD+RW it does quite well. But so does "dd" too.)
If you use wodim with CD media and experience failure, then it is in
most cases due to bad drve or medium.
But a wodim failure with DVD or BD can mean anything.
----------------------------------------------------------------------
Hm. Another user "jmtd" is editing in BurnCd.
Now i am curious whether the wodim-DVD-BD statement will be changed too.
Nevertheless, i plan to defend my version duely, unless a wodim maintainer
shows up and promises to take care of the bugs and code shortcommings.
I would be willing to help.
Have a nice day :)
Thomas
Reply to: