svn commit: r187609 - head/bin/dd

[Giorgos Keramidas]

Author: keramida (doc committer)
Date: Fri Jan 23 03:46:44 2009
New Revision: 187609
URL: http://svn.freebsd.org/changeset/base/187609

Log:
  Add an example of using bs=2048 to duplicate data CD-ROMs.
  
  This should be a bit useful for users who look at the manpage and
  then try to copy data CD-ROM disks using dd.  A lot of us know
  that bs=2048 is required, but it still manages to cause a bit of
  grief to those who haven't heard about it.
  
  PR:		bin/130857
  Submitted by:	Tri Brotoharsono < mail at tribrotoharsono.net >
  MFC after:	3 days

Modified:
  head/bin/dd/dd.1

Modified: head/bin/dd/dd.1
==============================================================================
--- head/bin/dd/dd.1	Fri Jan 23 03:15:28 2009	(r187608)
+++ head/bin/dd/dd.1	Fri Jan 23 03:46:44 2009	(r187609)
@@ -392,6 +392,11 @@ Remove parity bit from a file:
 Check for (even) parity errors on a file:
 .Pp
 .Dl "dd if=file conv=pareven | cmp -x - file"
+.Pp
+To create an image of a Mode-1 CD-ROM, which is a commonly used format
+for data CD-ROM disks, use a block size of 2048 bytes:
+.Pp
+.Dl "dd if=/dev/acd0 of=filename.iso bs=2048"
 .Sh SEE ALSO
 .Xr cp 1 ,
 .Xr mt 1 ,