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<TITLE>The Linux SCSI programming HOWTO: Opening The Device</TITLE>
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<H2><A NAME="s7">7. Opening The Device</A></H2>
<P>A generic device has to be opened for read and write access:
<P>
<BLOCKQUOTE><CODE>
<PRE>
int fd = open (device_name, O_RDWR);
</PRE>
</CODE></BLOCKQUOTE>
<P>(This is the case even for a read-only hardware device such as a cdrom
drive).
<P>We have to perform a <CODE>write</CODE> to send the command and a <CODE>read</CODE>
to get back any results. In the case of an error the return code is
negative (see section
<A HREF="SCSI-Programming-HOWTO-21.html#sec-errorhandling">sec-errorhandling</A>
for a complete list).
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