Hitchhiker's Guide to Openbsd

I want to write a CD here! Can we get on with it?
Before proceeding, it is a good idea to keep a few words of advice in mind: 
●
Do not run any disk-intensive jobs while writing a CD/DVD. Doing this will reduce the 
throughput to your CD/DVD writer. If the throughput drops below what the writer is expecting 
for too long, its buffer will run empty. This phenomenon is also known as a "buffer underrun". 
●
Prevent shocks during writing as this may cause the laser beam to drift from its track, which may 
lead to errors on the disc. 
●
Not every DVD writer supports every DVD format, see below. 
13.10.2 - Writing CDs
Creating data CD-ROMs
First, you will want to create an ISO 9660 filesystem to put on a CD-ROM. To do this you can use the 
mkhybrid(8)
 utility in the base system, or the mkisofs utility which comes with the cdrtools 
package
and 
which does a better job with large file trees. In the examples below, we will use mkhybrid, although 
mkisofs usage is very similar. 
As an example usage, let's say I wanted to store the OpenBSD kernel sources in an ISO 9660 image: 
$ mkhybrid -R -o sys.iso /usr/src/sys
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13 - Multimedia
Using ALTQ_RMC.000;1 for /usr/src/sys/altq/
altq_rmclass_debug.h (altq_rmclass.h)
...
Using IEEE8021.00H;1 for /usr/src/sys/net80211/
ieee80211_amrr.c (ieee80211.c)
10.89% done, estimate finish Sat Nov 3 08:01:23 2007
21.78% done, estimate finish Sat Nov 3 08:01:28 2007
...
87.12% done, estimate finish Sat Nov 3 08:01:31 2007
98.01% done, estimate finish Sat Nov 3 08:01:32 2007
Total translation table size: 0
Total rockridge attributes bytes: 896209
Total directory bytes: 2586624
Path table size(bytes): 11886
Max brk space used 0
45919 extents written (89 Mb)
The 
-R
option tells 
mkhybrid
to create Rock Ridge extensions in the ISO 9660 image. The Rock 
Ridge Interchange Protocol was created to support POSIX filesystem semantics in ISO 9660 
filesystems, such as longer file names, ownerships, permissions, file links, soft links, device nodes, deep 
file hierarchies (more than 8 levels of subdirectories), etc. 
If you want the long file names on your CD-ROM to be readable on Windows or DOS systems, you 
should add the 
-J
flag to include Joliet extensions in the ISO 9660 image as well. 
After creating the filesystem, you can verify it by 
mounting the ISO 9660 image
. If all is well, you are 
now ready to burn the CD-R(W). The easiest way to do this is to use the 
cdio(1)
utility. 
If you are using multi-write media such as CD-RW, you will need to blank the media before burning it. 
# cdio -f cd1c blank
You are now ready to burn the image created in the above example to a blank CD-R(W). You could use 
a command similar to: 
# cdio -f cd1c tao sys.iso
With the options specified above, we're asking cdio to use the second CD-ROM device as the CD writer. 
To verify whether the CD-ROM has been written correctly, you can mount it and check whether 
everything is there. To mount the filesystem, you should use the block device for the CD-ROM drive, 
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13 - Multimedia
which in this case is still the CD writer: 
# mount /dev/cd1c /mnt/cdrom