cd-writing-howto-4.html

Linux初学者最好的老师就是howto了。相当于函数man。

 * However perhaps it is legal to switch on an
 * already connected device. It is perhaps not
 * guaranteed this device doesn't corrupt an ongoing data transfer.
 */
</pre> 
        </code> 
      </blockquote> 
      <p>Please note that this should only be used if your add SCSI-devices at  
      the end of the chain. Inserting new SCSI-devices into an existing chain  
      disturbs the naming of devices (directory /dev) and may destroy the  
      complete content of your harddisk. 
      <p>　
      <p>　
      <h2><a name="ss4.7">4.7 &quot;可以進行一對一的光碟複製？&quot;</a></h2> 
      <p>可以。不過你要注意的是如果當讀取光碟時有任何的錯誤發生，都可能令杪寫失敗。 
      <p>第一個情況：你有一個可寫光碟機和一個唯讀光碟機。你可以用以下的指令 
      <p>　 
      <blockquote> 
        <code> 
        <pre>cdwrite -v -D /dev/sgc --pad -b  $(isosize  /dev/scd0) /dev/scd0
or
cdrecord -v dev=3,0 speed=2 -isosize /dev/scd0
</pre> 
        </code> 
      </blockquote> 
      <p>你可以從<code>/dev/scd0</code> 讀取資料流然後直接經由<code>/dev/sgc</code>  
      寫入光碟中。 
      <p>第二個情況：你沒有另一個唯讀光碟。你便需要用可寫光碟機來讀取光碟： 
      <p>　 
      <blockquote> 
        <code> 
        <pre>dd if=/dev/scd0 of=cdimage bs=1c count=`isosize  /dev/scd0`
</pre> 
        </code> 
      </blockquote> 
      <p>這個指令等同於 <code>mkisofs</code>  
      ，所以你可以用第三章所提及的方法繼續餘下的工作。請注意這個方法是不適用於音樂光碟。 
      <p>　 
      <p>　 
      <h2><a name="ss4.8">4.8 &quot;Linux 可不可以讀取 Joliet 光碟？&quot;</a></h2> 
      <p>可以。最新的核心 (2.0.36 和以後) 已內置支援 joliet  
      格式。請記著你要在 /etc/fstab 中使用 iso9660 和 joliet  
      兩個選項。要取得更多資料，你可以看 <a href="http://www-plateau.cs.berkeley.edu/people/chaffee/joliet.html">http://www-plateau.cs.berkeley.edu/people/chaffee/joliet.html</a>. 
      <p>　
      <p>　
      <h2><a name="ss4.9">4.9 &quot;怎樣用可寫光碟機讀取光碟？&quot;</a></h2> 
      <p>就如同你使用普通唯讀光碟機一樣。沒有任何的特別。注意你要使用scd-devices  
      (唯讀光碟機) 來讀取光碟。以下便是在/etc/fstab  
      中的範例： 
      <p>　 
      <blockquote> 
        <code> 
        <pre>/dev/scd0  /cdrom  iso9660  ro,user,noauto  0  0
</pre> 
        </code> 
      </blockquote> 
      <p>　
      <p>　
      <h2><a name="ss4.10">4.10 &quot;怎樣放多些資料到光碟中？&quot;</a></h2> 
      <p>用 <code>bzip2</code> 以取代其他的壓縮器好像 <code>gzip</code>  
      或 <code>pkzip</code>。這會節省30%的磁碟空間。你可以在以下地方下載 
      <p>　 
      <blockquote> 
        <a href="http://www.muraroa.demon.co.uk/">http://www.muraroa.demon.co.uk/</a> 
        <p>　</p>
      </blockquote>
      <p>Instead of writing a true audio-CD, you can optionally convert your  
      wav-audio-files into mp3-audio-files and store them on a ISO-9660  
      filesystem as regular files. Usually MPEG III gives you a compression of  
      1:10. 
      <p>Of course, most CD-players are not able to read files... this is the  
      drawback. On the other hand, why not running the music for your next party  
      from harddisk? 18 Gbyte are enough for 3000-4000 titles. :-) 
      <p>A software MPEG III-encoder is available from 
      <blockquote> 
        <a href="http://www.stud.ifi.uio.no/~larsi/other/8hz-mp3-cheng.tar.gz">http://www.stud.ifi.uio.no/~larsi/other/8hz-mp3-cheng.tar.gz</a> 
        <p>　</p>
      </blockquote>
      <p>A MPEG III-player is available from 
      <blockquote> 
        <a href="http://homepages.uni-tuebingen.de/student/michael.hipp/mpg123/">http://homepages.uni-tuebingen.de/student/michael.hipp/mpg123/</a> 
        <p>　</p>
      </blockquote>
      <p>For recorded speech, you may want to try to reduce its size using <code>shorten</code>  
      or &quot;GSM lossy speech compression&quot;: 
      <p>　
      <blockquote>
        <a href="ftp://svr-ftp.eng.cam.ac.uk/pub/comp.speech/">ftp://svr-ftp.eng.cam.ac.uk/pub/comp.speech/</a>
        <p><a href="http://kbs.cs.tu-berlin.de/~jutta/toast.html">http://kbs.cs.tu-berlin.de/~jutta/toast.html</a>
        <p>　</p>
      </blockquote>
      <p>　
      <p>　
      <h2><a name="ss4.11">4.11 &quot;How to make bootable CD-ROMs?&quot;</a></h2> 
      <p>You must have an 1.44 MB bootable floppy-disk. Create an exact image of  
      this floppy-disk by issuing the command 
      <p>　
      <blockquote>
        <code>
        <pre>dd if=/dev/fd0 of=boot.img bs=18k
</pre>
        </code>
      </blockquote>
      <p>Place this floppy-image into the directory holding the collection of 
      your files (or into a subdirectory of it, just as you like). Tell mkisofs 
      about this file with the option '-b' and also use '-c'. For details read 
      the file README.eltorito in the mkisofs-distribution.
      <p>An interesting application for a custom bootable CD is as a virus-safe 
      DOS- or Windows-system. It saves you the money for the harddisks (if you 
      have a network and use samba to put the user-data on a fileserver). 
      However, this is purely theoretical as nobody reported an actual recipe to 
      me.
      <p>Some details about the bootable RedHat CD-ROM is available from <a href="http://www.channel1.com/users/rodsmith/rhjol-technical.html">http://www.channel1.com/users/rodsmith/rhjol-technical.html</a>.
      <p>　
      <p>　
      <h2><a name="ss4.12">4.12 &quot;How to make CD-ROMs writable  
      somehow?&quot;</a></h2> 
      <p>There is an <i>overlay-filesystem</i> available for Linux, which is  
      mounted over the CD-ROM and intercepts all writing operations. New and  
      modified files are stored elsewhere, but for the user it looks like the  
      CD-ROM is modified. For more information, see <a href="http://home.att.net/~artnaseef/ovlfs/ovlfs.html">http://home.att.net/~artnaseef/ovlfs/ovlfs.html</a>. 
      <p>If that is not enough for your needs: wait for the UDF-filesystem to be  
      supported by Linux or help developing it (see <a href="http://trylinux.com/projects/udf/">http://trylinux.com/projects/udf/</a>. 
      <p>　
      <h2><a name="ss4.13">4.13 &quot;Is it possible to use several writers at  
      once?&quot;</a></h2> 
      <p>Yes. However, it has been only tested with two writers yet. And you  
      need a kernel patch for more buffers in the SCSI-generic driver ( <a href="ftp://ftp.fokus.gmd.de/pub/unix/cdrecord/alpha">ftp://ftp.fokus.gmd.de/pub/unix/cdrecord/alpha</a>). 
      <p>　
      <p>　
      <h2><a name="ss4.14">4.14 &quot;Which media is the best?&quot;</a></h2> 
      <p>The german computer magazine &quot;c't&quot; had a list of tips  
      regarding the blank CD-Rs in their november 1996 issue: 
      <p>　
      <ul>
        <li>&quot;No-name&quot; discs are generally not of highest quality and  
          should better not be used. 
        <li>If a recordable CD is defective, this is likely to apply to the  
          whole batch (if you bought more than one at a time); maybe you are  
          lucky and can at least use the first 500MB of such CD-Rs ... 
        <li>Don't touch the CD-Rs at their shimmering side before writing.</li> 
      </ul> 
      <p>　
      <p>　
      <hr>
      <a href="CD-Writing-HOWTO-5.html"><img alt="Next" src="next.gif" width="16" height="16"></a> <a href="CD-Writing-HOWTO-3.html"><img alt="Previous" src="prev.gif" width="16" height="16"></a> 
      <a href="CD-Writing-HOWTO.html#toc4"><img alt="Contents" src="toc.gif" width="16" height="16"></a></td>
  </table>

</body>

</html>