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@@ -64,75 +64,9 @@ their respective function and parameters are specified in <xref
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</refsect1>
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</refsect1>
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<refsect1>
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<refsect1>
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- <title>Return Value</title>
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-
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- <para>On success the <function>ioctl()</function> function returns
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-<returnvalue>0</returnvalue> and does not reset the
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-<varname>errno</varname> variable. On failure
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-<returnvalue>-1</returnvalue> is returned, when the ioctl takes an
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-output or read/write parameter it remains unmodified, and the
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-<varname>errno</varname> variable is set appropriately. See below for
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-possible error codes. Generic errors like <errorcode>EBADF</errorcode>
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-or <errorcode>EFAULT</errorcode> are not listed in the sections
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-discussing individual ioctl requests.</para>
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- <para>Note ioctls may return undefined error codes. Since errors
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-may have side effects such as a driver reset applications should
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-abort on unexpected errors.</para>
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-
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- <variablelist>
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- <varlistentry>
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- <term><errorcode>EBADF</errorcode></term>
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- <listitem>
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- <para><parameter>fd</parameter> is not a valid open file
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-descriptor.</para>
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- </listitem>
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- </varlistentry>
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- <varlistentry>
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- <term><errorcode>EBUSY</errorcode></term>
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- <listitem>
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- <para>The property cannot be changed right now. Typically
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-this error code is returned when I/O is in progress or the driver
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-supports multiple opens and another process locked the property.</para>
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- </listitem>
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- </varlistentry>
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- <varlistentry>
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- <term><errorcode>EFAULT</errorcode></term>
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- <listitem>
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- <para><parameter>argp</parameter> references an inaccessible
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-memory area.</para>
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- </listitem>
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- </varlistentry>
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- <varlistentry>
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- <term><errorcode>ENOTTY</errorcode></term>
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- <listitem>
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- <para><parameter>fd</parameter> is not associated with a
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-character special device.</para>
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- </listitem>
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- </varlistentry>
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- <varlistentry>
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- <term><errorcode>EINVAL</errorcode></term>
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- <listitem>
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- <para>The <parameter>request</parameter> or the data pointed
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-to by <parameter>argp</parameter> is not valid. This is a very common
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-error code, see the individual ioctl requests listed in <xref
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- linkend="user-func" /> for actual causes.</para>
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- </listitem>
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- </varlistentry>
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- <varlistentry>
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- <term><errorcode>ENOMEM</errorcode></term>
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- <listitem>
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- <para>Not enough physical or virtual memory was available to
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-complete the request.</para>
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- </listitem>
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- </varlistentry>
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- <varlistentry>
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- <term><errorcode>ERANGE</errorcode></term>
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- <listitem>
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- <para>The application attempted to set a control with the
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-&VIDIOC-S-CTRL; ioctl to a value which is out of bounds.</para>
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- </listitem>
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- </varlistentry>
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- </variablelist>
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+ &return-value;
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+ <para>When an ioctl that takes an output or read/write parameter fails,
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+ the parameter remains unmodified.</para>
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</refsect1>
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</refsect1>
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</refentry>
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</refentry>
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