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<a name="File_002dI_002fO-Examples"></a>
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<a name="File_002dI_002fO-Examples-1"></a>
<h4 class="subsection">E.13.10 File-I/O Examples</h4>
<a name="index-file_002di_002fo-examples"></a>

<p>Example sequence of a write call, file descriptor 3, buffer is at target
address 0x1234, 6 bytes should be written:
</p>
<div class="smallexample">
<pre class="smallexample">&lt;- <code>Fwrite,3,1234,6</code>
<em>request memory read from target</em>
-&gt; <code>m1234,6</code>
&lt;- XXXXXX
<em>return &quot;6 bytes written&quot;</em>
-&gt; <code>F6</code>
</pre></div>

<p>Example sequence of a read call, file descriptor 3, buffer is at target
address 0x1234, 6 bytes should be read:
</p>
<div class="smallexample">
<pre class="smallexample">&lt;- <code>Fread,3,1234,6</code>
<em>request memory write to target</em>
-&gt; <code>X1234,6:XXXXXX</code>
<em>return &quot;6 bytes read&quot;</em>
-&gt; <code>F6</code>
</pre></div>

<p>Example sequence of a read call, call fails on the host due to invalid
file descriptor (<code>EBADF</code>):
</p>
<div class="smallexample">
<pre class="smallexample">&lt;- <code>Fread,3,1234,6</code>
-&gt; <code>F-1,9</code>
</pre></div>

<p>Example sequence of a read call, user presses <kbd>Ctrl-c</kbd> before syscall on
host is called:
</p>
<div class="smallexample">
<pre class="smallexample">&lt;- <code>Fread,3,1234,6</code>
-&gt; <code>F-1,4,C</code>
&lt;- <code>T02</code>
</pre></div>

<p>Example sequence of a read call, user presses <kbd>Ctrl-c</kbd> after syscall on
host is called:
</p>
<div class="smallexample">
<pre class="smallexample">&lt;- <code>Fread,3,1234,6</code>
-&gt; <code>X1234,6:XXXXXX</code>
&lt;- <code>T02</code>
</pre></div>


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