Corrections and updates of documentation

xorriso/xorrisofs.1

@@ -9,7 +9,7 @@
 .\" First parameter, NAME, should be all caps
 .\" Second parameter, SECTION, should be 1-8, maybe w/ subsection
 .\" other parameters are allowed: see man(7), man(1)
-.TH XORRISOFS 1 "Mar 06, 2011"
+.TH XORRISOFS 1 "Mar 09, 2011"
 .\" Please adjust this date whenever revising the manpage.
 .\"
 .\" Some roff macros, for reference:
@@ -176,14 +176,19 @@ on the intended media.
 .br
 Both values can be inquired from optical media by help of burn programs
 and cdrecord option -msinfo. xorriso itself can obtain it in its
-cdrecord emulation:
+cdrecord emulation. Do not let it load the drive, but rather do this manually
+or by a program like dd which reads a few bytes. Only then it is sure that
+the device driver knows the true readable size of the media.
 .br
- values=$(xorriso -as cdrecord dev=/dev/... -msinfo)
- echo $values
+  dd if=/dev/... count=1 >/dev/null 2>&1
+.br
+  values=$(xorriso -as cdrecord dev=/dev/... -msinfo)
+.br
+  echo $values
 .br
 Option -C may be used without option -M to create an ISO image from
 scratch and prepare it for being finally written to a block address
-other than 0. Parameter last_session_start should then be set to 0.
+other than 0. Parameter last_session_start must then be set to 0.
 .TP
 \fB\-cdrecord-params\fR last_session_start,next_writeable_address
 Alias of -C.
@@ -1114,6 +1119,12 @@ yields in the ISO image:
   /with_=_and_\\/file
 .SS
 .B Perform multi-session runs
+This example works for multi-session media only:
+CD-R[W], DVD-R[W], DVD+R, BD-R.
+Add cdrskin option --grow_overwriteable_iso
+to all -as cdrecord runs
+in order to enable multi-session emulation on overwriteable media.
+.br
 The first session is written like this:
 .br
   $ xorrisofs -graft-points \\
@@ -1123,23 +1134,25 @@ The first session is written like this:
     | xorriso -as cdrecord -v dev=/dev/sr0 blank=fast -multi -eject - 
 .br
 Follow-up sessions are written like this:
+.br
+  $ dd if=/dev/sr0 count=1 >/dev/null 2>&1
 .br
   $ m=$(xorriso -as cdrecord dev=/dev/sr0 -msinfo)
 .br
   $ xorrisofs -M /dev/sr0 -C $m -graft-points \\
 .br
-              /tree2/=prepared_for_iso/tree2 \\
+              /tree2=prepared_for_iso/tree2 \\
 .br
     | xorriso -as cdrecord -v dev=/dev/sr0 -waiti -multi -eject -
 .br
 Always eject the drive tray between sessions. The old sessions
 get read via /dev/sr0. Its device driver might not be aware
 of the changed content before it loads the media again.
+In this case the previous session would not be loaded and the
+new session would contain only the newly added files.
 .br
-This example works for multi-session media only.
-Add cdrskin option --grow_overwriteable_iso
-to all -as cdrecord runs
-in order to enable multi-session emulation on overwriteable media.
+For the same reason do not let xorriso -as cdrecord load the media,
+but rather do this manually or by a program that reads from /dev/sr0.
 .SS
 .B Let xorrisofs work underneath growisofs
 growisofs expects an ISO formatter program which understands options -C and
@@ -1163,9 +1176,17 @@ use of all xorriso commands. growisofs dislikes options which
 start with "-o" but -outdev must be set to "-".
 So use "outdev" instead:
 .br
-  $ growisofs -Z /dev/dvd -- outdev - -update_r /my/files /files
+  $ growisofs -Z /dev/dvd --for_backup -- \\
 .br
-  $ growisofs -M /dev/dvd -- outdev - -update_r /my/files /files
+              outdev - -update_r /my/files /files
+.br
+  $ growisofs -M /dev/dvd --for_backup -- \\
+.br
+              outdev - -update_r /my/files /files
+.br
+Note that --for_backup is given in the mkisofs emulation.
+To preserve the recorded extra data it must already be in effect, when
+the emulation loads the image.
 .SS
 .B Incremental backup of a few directory trees
 This changes the directory trees /open_source_project and /personal_mail
@@ -1183,6 +1204,11 @@ To be used several times on the same media, whenever an update of
 the two disk trees to the media is desired. Begin with blank media and start
 a new blank media when the run fails due to lack of remaining space on
 the old one.
+.br
+Do not let xorriso -as cdrecord load the media,
+but rather do this manually or by a program that reads from /dev/sr0.
+.br
+  $ dd if=/dev/sr0 count=1 >/dev/null 2>&1
 .br
   $ msinfo=$(xorriso -as cdrecord dev=/dev/sr0 -msinfo)
 .br
@@ -1275,7 +1301,12 @@ With the first session:
 .br
 .sp 1
 With the second session, option -old-root refers to /session1 and the
-new -root is /session2:
+new -root is /session2.
+.br
+Do not let xorriso -as cdrecord load the media,
+but rather do this manually or by a program that reads from /dev/sr0.
+.br
+  $ dd if=/dev/sr0 count=1 >/dev/null 2>&1
 .br
   $ msinfo=$(xorriso -as cdrecord dev=/dev/sr0 -msinfo)
 .br
@@ -1314,9 +1345,13 @@ The prescribed mkisofs options can be used unchanged with xorrisofs:
 .br
       ./CD_root
 .br
+Put it on CD by a burn program. E.g.:
+.br
+  $ xorriso -as cdrecord -v dev=/dev/sr0 blank=as_needed output.iso
+.br
 .sp 1
 The image from above example will boot from CD, DVD or BD, but not from
-USB stick or orther hard-disk-like devices. This can be done by help of an
+USB stick or other hard-disk-like devices. This can be done by help of an
 isohybrid MBR. Syslinux provides matching template files
 as isohdp[fp]x*.bin . E.g. /usr/lib/syslinux/isohdpfx.bin .
 .br
@@ -1327,6 +1362,8 @@ tools for partitioning and formatting.
 .br
 The image from the following example will be prepared for booting via MBR
 and its first parttion will start at hard disk block 64.
+.br
+It will also boot from optical media.
 .br
   $ xorrisofs -o output.iso \\
       -b isolinux/isolinux.bin -c isolinux/boot.cat \\