trunk/readom/readom.1

.\" @(#)readom.1        1.23 06/01/12 Copyright 1996-2006 J. Schilling
.\" 
.\" Modified version of readcd.1 by J. Schilling, 11/2006
.\" 
.\" This program is free software; you can redistribute it and/or modify
.\" it under the terms of the GNU General Public License version 2
.\" as published by the Free Software Foundation.
.\"
.\" The GNU General Public License's references to "object code"
.\" and "executables" are to be interpreted as the output of any
.\" document formatting or typesetting system, including
.\" intermediate and printed output.
.\"
.\" This manual is distributed in the hope that it will be useful,
.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
.\" GNU General Public License for more details.
.\"
.\" You should have received a copy of the GNU General Public License along with
.\" this program; see the file COPYING.  If not, write to the Free Software
.\" Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
.if t .ds a \v'-0.55m'\h'0.00n'\z.\h'0.40n'\z.\v'0.55m'\h'-0.40n'a
.if t .ds o \v'-0.55m'\h'0.00n'\z.\h'0.45n'\z.\v'0.55m'\h'-0.45n'o
.if t .ds u \v'-0.55m'\h'0.00n'\z.\h'0.40n'\z.\v'0.55m'\h'-0.40n'u
.if t .ds A \v'-0.77m'\h'0.25n'\z.\h'0.45n'\z.\v'0.77m'\h'-0.70n'A
.if t .ds O \v'-0.77m'\h'0.25n'\z.\h'0.45n'\z.\v'0.77m'\h'-0.70n'O
.if t .ds U \v'-0.77m'\h'0.30n'\z.\h'0.45n'\z.\v'0.77m'\h'-0.75n'U
.if t .ds s \\(*b
.if t .ds S SS
.if n .ds a ae
.if n .ds o oe
.if n .ds u ue
.if n .ds s sz
.TH READOM 1 "Version 2.0" "J\*org Schilling" "Schily\'s USER COMMANDS"
.SH NAME
readom \- read or write data Compact Discs
.SH SYNOPSIS
.B readom
.BI dev= device
[
.I options
]

.SH DESCRIPTION
.B Readom
is used to read or write Compact Discs.
.PP
The
.I device
refers to a device location similar to the one used in the wodim command. Refer to its manpage for details.
.PP
Also note that this version of readom uses a modified libusal library which has
a different behaviour compared to the one distributed by its original author.

.SH OPTIONS
.PP
If no options except the 
.I dev=
option have been specified, 
.B readom
goes into interactive mode.
Select a primary function and then follow the instructions.
.PP
.TP
.B \-version
Print version information and exit.
.TP
.BI dev= target
Sets the SCSI target for the drive, see notes above.
A typical device specification is
.BI dev= 6,0
\&.
If a filename must be provided together with the numerical target 
specification, the filename is implementation specific.
The correct filename in this case can be found in the system specific
manuals of the target operating system.
On a 
.I FreeBSD
system without 
.I CAM
support, you need to use the control device (e.g.
.IR /dev/rcd0.ctl ).
A correct device specification in this case may be
.BI dev= /dev/rcd0.ctl:@
\&.
.sp
On Linux, drives connected to a parallel port adapter are mapped
to a virtual SCSI bus. Different adapters are mapped to different
targets on this virtual SCSI bus.
.sp
If no 
.I dev
option is present, 
.B readom
will try to get the device from the 
.B CDR_DEVICE
environment.
.sp
If the argument to the
.B dev=
option does not contain the characters ',', '/', '@' or ':',
it is interpreted as an label name that may be found in the file
/etc/wodim.conf (see FILES section).
.TP
.BI timeout= #
Set the default SCSI command timeout value to 
.IR # " seconds.
The default SCSI command timeout is the minimum timeout used for sending
SCSI commands.
If a SCSI command fails due to a timeout, you may try to raise the
default SCSI command timeout above the timeout value of the failed command.
If the command runs correctly with a raised command timeout,
please report the better timeout value and the corresponding command to 
the author of the program.
If no 
.I timeout 
option is present, a default timeout of 40 seconds is used.
.TP
.BI debug= "#, " -d
Set the misc debug value to # (with debug=#) or increment
the misc debug level by one (with -d). If you specify
.I -dd,
this equals to 
.BI debug= 2.
This may help to find problems while opening a driver for libusal.
as well as with sector sizes and sector types.
Using
.B \-debug
slows down the process and may be the reason for a buffer underrun.
.TP
.BR kdebug= "#, " kd= #
Tell the 
.BR usal -driver
to modify the kernel debug value while SCSI commands are running.
.TP
.BR \-silent ", " \-s
Do not print out a status report for failed SCSI commands.
.TP
.B \-v
Increment the level of general verbosity by one.
This is used e.g. to display the progress of the process.
.TP
.B \-V
Increment the verbose level with respect of SCSI command transport by one.
This helps to debug problems
during the process, that occur in the CD-Recorder. 
If you get incomprehensible error messages you should use this flag
to get more detailed output.
.B \-VV
will show data buffer content in addition.
Using
.B \-V
or
.B \-VV
slows down the process.
.TP
.BI f= file
Specify the filename where the output should be written or the inout should
be taken from. Using '-' as filename will cause
.B readom
to use 
.BR stdout " resp. " stdin .
.TP
.B \-w
Switch to write mode. If this option is not present,
.B readom
reads from the specified device.
.TP
.B \-c2scan
Scans the whole CD or the range specified by the 
.BI sectors= range
for C2 errors. C2 errors are errors that are uncorrectable after the second
stage of the 24/28 + 28/32 Reed Solomon correction system at audio level
(2352 bytes sector size). If an audio CD has C2 errors, interpolation is needed
to hide the errors. If a data CD has C2 errors, these errors are in most
cases corrected by the ECC/EDC code that makes 2352 bytes out of 2048 data
bytes. The ECC/EDC code should be able to correct about 100 C2 error bytes
per sector.
.sp
If you find C2 errors you may want to reduce the speed using the
.B speed=
option as C2 errors may be a result of dynamic unbalance on the medium.
.TP
.B \-scanbus
Scan all SCSI devices on all SCSI busses and print the inquiry
strings. This option may be used to find SCSI address of the 
devices on a system.
The numbers printed out as labels are computed by: 
.B "bus * 100 + target
.TP
.BI sectors= range
Specify a sector range that should be read.
The range is specified by the starting sector number, a minus sign and the
ending sector number.
The end sector is not included in the list, so 
.BR sectors= 0-0
will not read anything and may be used to check for a CD in the drive.
.TP
.BR speed= #
Set the speed factor of the read or write process to #.
# is an integer, representing a multiple of the audio speed.
This is about 150 KB/s for CD-ROM and about 172 KB/s for CD-Audio.
If no 
.I speed
option is present, 
.B readom
will use maximum speed.
Only MMC compliant drives will benefit from this option.
The speed of non MMC drives is not changed.
.sp
Using a lower speed may increase the readability of a CD or DVD.
.TP
.BR ts= #
Set the maximum transfer size for a single SCSI command to #.
The syntax for the 
.B ts=
option is the same as for wodim fs=# or sdd bs=#.
.sp
If no 
.B ts=
option has been specified,
.B readom
defaults to a transfer size of 256 kB. If libusal gets lower values from the
operating system, the value is reduced to the maximum value that is possible
with the current operating system.
Sometimes, it may help to further reduce the transfer size or to enhance it,
but note that it may take a long time to find a better value by experimenting
with the
.B ts=
option.
.TP
.B \-notrunc
Do not truncate the output file when opening it.
.TP
.B \-fulltoc
Retrieve a full TOC from the current disk and print it in hex.
.TP
.B \-clone
Do a clone read. Read the CD with all sub-channel data and a full TOC.
The full TOC data will be put into a file with similar name as with the
.B f=
option but the suffix 
.B .toc
added.
.TP
.B \-noerror
Do not abort if the high level error checking in
.B readom
found an uncorrectable error in the data stream.
.TP
.B \-nocorr
Switch the drive into a mode where it ignores read errors in data sectors that
are a result of uncorrectable ECC/EDC errors before reading.
If
.B readom
completes, the error recovery mode of the drive is switched back to the remembered 
old mode.
.TP
.BI retries= #
Set the retry count for high level retries in
.B readom
to 
.IR # .
The default is to do 128 retries which may be too much if you like to read a CD
with many unreadable sectors.
.TP
.B \-overhead
Meter the SCSI command overhead time.
This is done by executing several commands 1000 times and printing the
total time used. If you divide the displayed times by 1000, you get 
the average overhead time for a single command.
.TP
.BR meshpoints= #
Print read-speed at # locations.
The purpose of this option is to create a list of read speed values suitable
for e.g.
.BR gnuplot .
The speed values are calculated assuming that 1000 bytes are one kilobyte
as documented in the SCSI standard.
The ouput data created for this purpose is written to 
.IR stdout .
.TP
.B \-factor
Output the speed values for
.BR meshpoints= #
as factor based on 
.I "single speed
of the current medium.
This only works if
.B readom
is able to determine the current medium type.
.SH EXAMPLES
.PP
For all examples below, it will be assumed that the drive is
connected to the primary SCSI bus of the machine. The SCSI target id is
set to 2.
.PP
To read the complete media from a CD-ROM writing the data to the file
.IR cdimage.raw :
.PP
    readom dev=2,0 f=cdimage.raw
.PP
To read sectors from range 150 ... 10000 from a CD-ROM writing the data to the file
.IR cdimage.raw :
.PP
    readom dev=2,0 sectors=150-10000 f=cdimage.raw
.PP
To write the data from the file
.I cdimage.raw
(e.g. a filesystem image from 
.BR mkisofs )
to a DVD-RAM, call:
.PP
    readom dev=2,0 -w f=cdimage.raw

.SH ENVIRONMENT
.TP
.B RSH
If the 
.B RSH
environment is present, the remote connection will not be created via
.BR rcmd (3)
but by calling the program pointed to by
.BR RSH .
Use e.g. 
.BR RSH= /usr/bin/ssh
to create a secure shell connection.
.sp
Note that this forces 
.B wodim
to create a pipe to the 
.B rsh(1)
program and disallows
.B wodim
to directly access the network socket to the remote server.
This makes it impossible to set up performance parameters and slows down
the connection compared to a 
.B root
initiated
.B rcmd(3)
connection.
.TP
.B RSCSI
If the 
.B RSCSI
environment is present, the remote SCSI server will not be the program
.B /opt/schily/sbin/rscsi
but the program pointed to by
.BR RSCSI .
Note that the remote SCSI server program name will be ignored if you log in
using an account that has been created with a remote SCSI server program as
login shell.
.SH SEE ALSO
.BR wodim (1),
.BR mkisofs (1),
.BR rcmd (3),
.BR ssh (1).

.SH NOTES
.PP
Unless you want to risk getting problems,
.B readom
should be run as root. If you don't want to allow users to become root on your system,
.B readom
may safely be installed suid root.
For more information see the additional notes of your system/program
distribution or README.suidroot which is part of the Cdrkit source.
.PP
Documentation of the
.B wodim
program contains more technical details which could also apply to
.B readom.

.SH DIAGNOSTICS
.PP
.PP
A typical error message for a SCSI command looks like:
.sp
.RS
.nf
readom: I/O error. test unit ready: scsi sendcmd: no error
CDB:  00 20 00 00 00 00
status: 0x2 (CHECK CONDITION)
Sense Bytes: 70 00 05 00 00 00 00 0A 00 00 00 00 25 00 00 00 00 00
Sense Key: 0x5 Illegal Request, Segment 0
Sense Code: 0x25 Qual 0x00 (logical unit not supported) Fru 0x0
Sense flags: Blk 0 (not valid)
cmd finished after 0.002s timeout 40s
.fi
.sp
.RE
The first line gives information about the transport of the command.
The text after the first colon gives the error text for the system call
from the view of the kernel. It usually is:
.B "I/O error
unless other problems happen. The next words contain a short description for
the SCSI command that fails. The rest of the line tells you if there were
any problems for the transport of the command over the SCSI bus.
.B "fatal error
means that it was not possible to transport the command (i.e. no device present
at the requested SCSI address).
.PP
The second line prints the SCSI command descriptor block for the failed command.
.PP
The third line gives information on the SCSI status code returned by the 
command, if the transport of the command succeeds. 
This is error information from the SCSI device.
.PP
The fourth line is a hex dump of the auto request sense information for the 
command.
.PP
The fifth line is the error text for the sense key if available, followed
by the segment number that is only valid if the command was a
.I copy
command. If the error message is not directly related to the current command,
the text
.I deferred error
is appended.
.PP
The sixth line is the error text for the sense code and the sense qualifier if available.
If the type of the device is known, the sense data is decoded from tables
in
.IR scsierrs.c " .
The text is followed by the error value for a field replaceable unit.
.PP
The seventh line prints the block number that is related to the failed command
and text for several error flags. The block number may not be valid.
.PP
The eight line reports the timeout set up for this command and the time
that the command really needed to complete.

.SH BUGS
.PP
The 
.B readom
program described here is the Cdrkit spinoff from the original
.B readcd
application (see AUTHOR section for details). It may contain bugs not present
in the original implementation.
.PP
It is definitely less portable than the original implementation.
.PP
For platform specific bugs, see the corresponding README.platform file in the
Cdrkit documentation (eg. README.linux).

.SH "MAILING LISTS
If you want to actively take part on the development of readom,
you may join the developer mailing list via this URL:
.sp
.B
http://alioth.debian.org/mail/?group_id=31006
.PP
The mail address of the list is:
.B
debburn-devel@lists.alioth.debian.org


.SH AUTHOR
.nf
J\*org Schilling
Seestr. 110
D-13353 Berlin
Germany
.fi

.PP
This is application is a spinoff from the original implementation of readcd delivered in
the cdrtools package [1] created by Joerg Schilling, who deserves the most credits
for its success. However, he is not involved into the development
of this spinoff and therefore he shall not be made responsible for any problem
caused by it. Do not try to get support from the original author!
.PP
Additional information can be found on:
.br
https://alioth.debian.org/projects/debburn/
.PP
If you have support questions, send them to
.PP
.B
debburn-devel@lists.alioth.debian.org
.br
.PP
If you have definitely found a bug, send a mail to this list or to
.PP
.B
submit@bugs.debian.org
.br
.PP
writing at least a short description into the Subject and "Package: cdrkit"
into the first line of the mail body.
.SH SOURCES
.PP
.br
[1] Cdrtools 2.01.01a08 from May 2006, http://cdrecord.berlios.de

1	.\" @(#)readom.1 1.23 06/01/12 Copyright 1996-2006 J. Schilling
2	.\"
3	.\" Modified version of readcd.1 by J. Schilling, 11/2006
4	.\"
5	.\" This program is free software; you can redistribute it and/or modify
6	.\" it under the terms of the GNU General Public License version 2
7	.\" as published by the Free Software Foundation.
8	.\"
9	.\" The GNU General Public License's references to "object code"
10	.\" and "executables" are to be interpreted as the output of any
11	.\" document formatting or typesetting system, including
12	.\" intermediate and printed output.
13	.\"
14	.\" This manual is distributed in the hope that it will be useful,
15	.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
16	.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17	.\" GNU General Public License for more details.
18	.\"
19	.\" You should have received a copy of the GNU General Public License along with
20	.\" this program; see the file COPYING. If not, write to the Free Software
21	.\" Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
22	.if t .ds a \v'-0.55m'\h'0.00n'\z.\h'0.40n'\z.\v'0.55m'\h'-0.40n'a
23	.if t .ds o \v'-0.55m'\h'0.00n'\z.\h'0.45n'\z.\v'0.55m'\h'-0.45n'o
24	.if t .ds u \v'-0.55m'\h'0.00n'\z.\h'0.40n'\z.\v'0.55m'\h'-0.40n'u
25	.if t .ds A \v'-0.77m'\h'0.25n'\z.\h'0.45n'\z.\v'0.77m'\h'-0.70n'A
26	.if t .ds O \v'-0.77m'\h'0.25n'\z.\h'0.45n'\z.\v'0.77m'\h'-0.70n'O
27	.if t .ds U \v'-0.77m'\h'0.30n'\z.\h'0.45n'\z.\v'0.77m'\h'-0.75n'U
28	.if t .ds s \\(*b
29	.if t .ds S SS
30	.if n .ds a ae
31	.if n .ds o oe
32	.if n .ds u ue
33	.if n .ds s sz
34	.TH READOM 1 "Version 2.0" "J\*org Schilling" "Schily\'s USER COMMANDS"
35	.SH NAME
36	readom \- read or write data Compact Discs
37	.SH SYNOPSIS
38	.B readom
39	.BI dev= device
40	[
41	.I options
42	]
43
44	.SH DESCRIPTION
45	.B Readom
46	is used to read or write Compact Discs.
47	.PP
48	The
49	.I device
50	refers to a device location similar to the one used in the wodim command. Refer to its manpage for details.
51	.PP
52	Also note that this version of readom uses a modified libusal library which has
53	a different behaviour compared to the one distributed by its original author.
54
55	.SH OPTIONS
56	.PP
57	If no options except the
58	.I dev=
59	option have been specified,
60	.B readom
61	goes into interactive mode.
62	Select a primary function and then follow the instructions.
63	.PP
64	.TP
65	.B \-version
66	Print version information and exit.
67	.TP
68	.BI dev= target
69	Sets the SCSI target for the drive, see notes above.
70	A typical device specification is
71	.BI dev= 6,0
72	\&.
73	If a filename must be provided together with the numerical target
74	specification, the filename is implementation specific.
75	The correct filename in this case can be found in the system specific
76	manuals of the target operating system.
77	On a
78	.I FreeBSD
79	system without
80	.I CAM
81	support, you need to use the control device (e.g.
82	.IR /dev/rcd0.ctl ).
83	A correct device specification in this case may be
84	.BI dev= /dev/rcd0.ctl:@
85	\&.
86	.sp
87	On Linux, drives connected to a parallel port adapter are mapped
88	to a virtual SCSI bus. Different adapters are mapped to different
89	targets on this virtual SCSI bus.
90	.sp
91	If no
92	.I dev
93	option is present,
94	.B readom
95	will try to get the device from the
96	.B CDR_DEVICE
97	environment.
98	.sp
99	If the argument to the
100	.B dev=
101	option does not contain the characters ',', '/', '@' or ':',
102	it is interpreted as an label name that may be found in the file
103	/etc/wodim.conf (see FILES section).
104	.TP
105	.BI timeout= #
106	Set the default SCSI command timeout value to
107	.IR # " seconds.
108	The default SCSI command timeout is the minimum timeout used for sending
109	SCSI commands.
110	If a SCSI command fails due to a timeout, you may try to raise the
111	default SCSI command timeout above the timeout value of the failed command.
112	If the command runs correctly with a raised command timeout,
113	please report the better timeout value and the corresponding command to
114	the author of the program.
115	If no
116	.I timeout
117	option is present, a default timeout of 40 seconds is used.
118	.TP
119	.BI debug= "#, " -d
120	Set the misc debug value to # (with debug=#) or increment
121	the misc debug level by one (with -d). If you specify
122	.I -dd,
123	this equals to
124	.BI debug= 2.
125	This may help to find problems while opening a driver for libusal.
126	as well as with sector sizes and sector types.
127	Using
128	.B \-debug
129	slows down the process and may be the reason for a buffer underrun.
130	.TP
131	.BR kdebug= "#, " kd= #
132	Tell the
133	.BR usal -driver
134	to modify the kernel debug value while SCSI commands are running.
135	.TP
136	.BR \-silent ", " \-s
137	Do not print out a status report for failed SCSI commands.
138	.TP
139	.B \-v
140	Increment the level of general verbosity by one.
141	This is used e.g. to display the progress of the process.
142	.TP
143	.B \-V
144	Increment the verbose level with respect of SCSI command transport by one.
145	This helps to debug problems
146	during the process, that occur in the CD-Recorder.
147	If you get incomprehensible error messages you should use this flag
148	to get more detailed output.
149	.B \-VV
150	will show data buffer content in addition.
151	Using
152	.B \-V
153	or
154	.B \-VV
155	slows down the process.
156	.TP
157	.BI f= file
158	Specify the filename where the output should be written or the inout should
159	be taken from. Using '-' as filename will cause
160	.B readom
161	to use
162	.BR stdout " resp. " stdin .
163	.TP
164	.B \-w
165	Switch to write mode. If this option is not present,
166	.B readom
167	reads from the specified device.
168	.TP
169	.B \-c2scan
170	Scans the whole CD or the range specified by the
171	.BI sectors= range
172	for C2 errors. C2 errors are errors that are uncorrectable after the second
173	stage of the 24/28 + 28/32 Reed Solomon correction system at audio level
174	(2352 bytes sector size). If an audio CD has C2 errors, interpolation is needed
175	to hide the errors. If a data CD has C2 errors, these errors are in most
176	cases corrected by the ECC/EDC code that makes 2352 bytes out of 2048 data
177	bytes. The ECC/EDC code should be able to correct about 100 C2 error bytes
178	per sector.
179	.sp
180	If you find C2 errors you may want to reduce the speed using the
181	.B speed=
182	option as C2 errors may be a result of dynamic unbalance on the medium.
183	.TP
184	.B \-scanbus
185	Scan all SCSI devices on all SCSI busses and print the inquiry
186	strings. This option may be used to find SCSI address of the
187	devices on a system.
188	The numbers printed out as labels are computed by:
189	.B "bus * 100 + target
190	.TP
191	.BI sectors= range
192	Specify a sector range that should be read.
193	The range is specified by the starting sector number, a minus sign and the
194	ending sector number.
195	The end sector is not included in the list, so
196	.BR sectors= 0-0
197	will not read anything and may be used to check for a CD in the drive.
198	.TP
199	.BR speed= #
200	Set the speed factor of the read or write process to #.
201	# is an integer, representing a multiple of the audio speed.
202	This is about 150 KB/s for CD-ROM and about 172 KB/s for CD-Audio.
203	If no
204	.I speed
205	option is present,
206	.B readom
207	will use maximum speed.
208	Only MMC compliant drives will benefit from this option.
209	The speed of non MMC drives is not changed.
210	.sp
211	Using a lower speed may increase the readability of a CD or DVD.
212	.TP
213	.BR ts= #
214	Set the maximum transfer size for a single SCSI command to #.
215	The syntax for the
216	.B ts=
217	option is the same as for wodim fs=# or sdd bs=#.
218	.sp
219	If no
220	.B ts=
221	option has been specified,
222	.B readom
223	defaults to a transfer size of 256 kB. If libusal gets lower values from the
224	operating system, the value is reduced to the maximum value that is possible
225	with the current operating system.
226	Sometimes, it may help to further reduce the transfer size or to enhance it,
227	but note that it may take a long time to find a better value by experimenting
228	with the
229	.B ts=
230	option.
231	.TP
232	.B \-notrunc
233	Do not truncate the output file when opening it.
234	.TP
235	.B \-fulltoc
236	Retrieve a full TOC from the current disk and print it in hex.
237	.TP
238	.B \-clone
239	Do a clone read. Read the CD with all sub-channel data and a full TOC.
240	The full TOC data will be put into a file with similar name as with the
241	.B f=
242	option but the suffix
243	.B .toc
244	added.
245	.TP
246	.B \-noerror
247	Do not abort if the high level error checking in
248	.B readom
249	found an uncorrectable error in the data stream.
250	.TP
251	.B \-nocorr
252	Switch the drive into a mode where it ignores read errors in data sectors that
253	are a result of uncorrectable ECC/EDC errors before reading.
254	If
255	.B readom
256	completes, the error recovery mode of the drive is switched back to the remembered
257	old mode.
258	.TP
259	.BI retries= #
260	Set the retry count for high level retries in
261	.B readom
262	to
263	.IR # .
264	The default is to do 128 retries which may be too much if you like to read a CD
265	with many unreadable sectors.
266	.TP
267	.B \-overhead
268	Meter the SCSI command overhead time.
269	This is done by executing several commands 1000 times and printing the
270	total time used. If you divide the displayed times by 1000, you get
271	the average overhead time for a single command.
272	.TP
273	.BR meshpoints= #
274	Print read-speed at # locations.
275	The purpose of this option is to create a list of read speed values suitable
276	for e.g.
277	.BR gnuplot .
278	The speed values are calculated assuming that 1000 bytes are one kilobyte
279	as documented in the SCSI standard.
280	The ouput data created for this purpose is written to
281	.IR stdout .
282	.TP
283	.B \-factor
284	Output the speed values for
285	.BR meshpoints= #
286	as factor based on
287	.I "single speed
288	of the current medium.
289	This only works if
290	.B readom
291	is able to determine the current medium type.
292	.SH EXAMPLES
293	.PP
294	For all examples below, it will be assumed that the drive is
295	connected to the primary SCSI bus of the machine. The SCSI target id is
296	set to 2.
297	.PP
298	To read the complete media from a CD-ROM writing the data to the file
299	.IR cdimage.raw :
300	.PP
301	readom dev=2,0 f=cdimage.raw
302	.PP
303	To read sectors from range 150 ... 10000 from a CD-ROM writing the data to the file
304	.IR cdimage.raw :
305	.PP
306	readom dev=2,0 sectors=150-10000 f=cdimage.raw
307	.PP
308	To write the data from the file
309	.I cdimage.raw
310	(e.g. a filesystem image from
311	.BR mkisofs )
312	to a DVD-RAM, call:
313	.PP
314	readom dev=2,0 -w f=cdimage.raw
315
316	.SH ENVIRONMENT
317	.TP
318	.B RSH
319	If the
320	.B RSH
321	environment is present, the remote connection will not be created via
322	.BR rcmd (3)
323	but by calling the program pointed to by
324	.BR RSH .
325	Use e.g.
326	.BR RSH= /usr/bin/ssh
327	to create a secure shell connection.
328	.sp
329	Note that this forces
330	.B wodim
331	to create a pipe to the
332	.B rsh(1)
333	program and disallows
334	.B wodim
335	to directly access the network socket to the remote server.
336	This makes it impossible to set up performance parameters and slows down
337	the connection compared to a
338	.B root
339	initiated
340	.B rcmd(3)
341	connection.
342	.TP
343	.B RSCSI
344	If the
345	.B RSCSI
346	environment is present, the remote SCSI server will not be the program
347	.B /opt/schily/sbin/rscsi
348	but the program pointed to by
349	.BR RSCSI .
350	Note that the remote SCSI server program name will be ignored if you log in
351	using an account that has been created with a remote SCSI server program as
352	login shell.
353	.SH SEE ALSO
354	.BR wodim (1),
355	.BR mkisofs (1),
356	.BR rcmd (3),
357	.BR ssh (1).
358
359	.SH NOTES
360	.PP
361	Unless you want to risk getting problems,
362	.B readom
363	should be run as root. If you don't want to allow users to become root on your system,
364	.B readom
365	may safely be installed suid root.
366	For more information see the additional notes of your system/program
367	distribution or README.suidroot which is part of the Cdrkit source.
368	.PP
369	Documentation of the
370	.B wodim
371	program contains more technical details which could also apply to
372	.B readom.
373
374	.SH DIAGNOSTICS
375	.PP
376	.PP
377	A typical error message for a SCSI command looks like:
378	.sp
379	.RS
380	.nf
381	readom: I/O error. test unit ready: scsi sendcmd: no error
382	CDB: 00 20 00 00 00 00
383	status: 0x2 (CHECK CONDITION)
384	Sense Bytes: 70 00 05 00 00 00 00 0A 00 00 00 00 25 00 00 00 00 00
385	Sense Key: 0x5 Illegal Request, Segment 0
386	Sense Code: 0x25 Qual 0x00 (logical unit not supported) Fru 0x0
387	Sense flags: Blk 0 (not valid)
388	cmd finished after 0.002s timeout 40s
389	.fi
390	.sp
391	.RE
392	The first line gives information about the transport of the command.
393	The text after the first colon gives the error text for the system call
394	from the view of the kernel. It usually is:
395	.B "I/O error
396	unless other problems happen. The next words contain a short description for
397	the SCSI command that fails. The rest of the line tells you if there were
398	any problems for the transport of the command over the SCSI bus.
399	.B "fatal error
400	means that it was not possible to transport the command (i.e. no device present
401	at the requested SCSI address).
402	.PP
403	The second line prints the SCSI command descriptor block for the failed command.
404	.PP
405	The third line gives information on the SCSI status code returned by the
406	command, if the transport of the command succeeds.
407	This is error information from the SCSI device.
408	.PP
409	The fourth line is a hex dump of the auto request sense information for the
410	command.
411	.PP
412	The fifth line is the error text for the sense key if available, followed
413	by the segment number that is only valid if the command was a
414	.I copy
415	command. If the error message is not directly related to the current command,
416	the text
417	.I deferred error
418	is appended.
419	.PP
420	The sixth line is the error text for the sense code and the sense qualifier if available.
421	If the type of the device is known, the sense data is decoded from tables
422	in
423	.IR scsierrs.c " .
424	The text is followed by the error value for a field replaceable unit.
425	.PP
426	The seventh line prints the block number that is related to the failed command
427	and text for several error flags. The block number may not be valid.
428	.PP
429	The eight line reports the timeout set up for this command and the time
430	that the command really needed to complete.
431
432	.SH BUGS
433	.PP
434	The
435	.B readom
436	program described here is the Cdrkit spinoff from the original
437	.B readcd
438	application (see AUTHOR section for details). It may contain bugs not present
439	in the original implementation.
440	.PP
441	It is definitely less portable than the original implementation.
442	.PP
443	For platform specific bugs, see the corresponding README.platform file in the
444	Cdrkit documentation (eg. README.linux).
445
446	.SH "MAILING LISTS
447	If you want to actively take part on the development of readom,
448	you may join the developer mailing list via this URL:
449	.sp
450	.B
451	http://alioth.debian.org/mail/?group_id=31006
452	.PP
453	The mail address of the list is:
454	.B
455	debburn-devel@lists.alioth.debian.org
456
457
458
459
460	.SH AUTHOR
461	.nf
462	J\*org Schilling
463	Seestr. 110
464	D-13353 Berlin
465	Germany
466	.fi
467
468	.PP
469	This is application is a spinoff from the original implementation of readcd delivered in
470	the cdrtools package [1] created by Joerg Schilling, who deserves the most credits
471	for its success. However, he is not involved into the development
472	of this spinoff and therefore he shall not be made responsible for any problem
473	caused by it. Do not try to get support from the original author!
474	.PP
475	Additional information can be found on:
476	.br
477	https://alioth.debian.org/projects/debburn/
478	.PP
479	If you have support questions, send them to
480	.PP
481	.B
482	debburn-devel@lists.alioth.debian.org
483	.br
484	.PP
485	If you have definitely found a bug, send a mail to this list or to
486	.PP
487	.B
488	submit@bugs.debian.org
489	.br
490	.PP
491	writing at least a short description into the Subject and "Package: cdrkit"
492	into the first line of the mail body.
493	.SH SOURCES
494	.PP
495	.br
496	[1] Cdrtools 2.01.01a08 from May 2006, http://cdrecord.berlios.de
497