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Next: <a href="List-of-Supported-Calls.html#List-of-Supported-Calls" accesskey="n" rel="next">List of Supported Calls</a>, Previous: <a href="The-Ctrl_002dC-Message.html#The-Ctrl_002dC-Message" accesskey="p" rel="prev">The Ctrl-C Message</a>, Up: <a href="File_002dI_002fO-Remote-Protocol-Extension.html#File_002dI_002fO-Remote-Protocol-Extension" accesskey="u" rel="up">File-I/O Remote Protocol Extension</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Console-I_002fO-1"></a>
<h4 class="subsection">E.13.6 Console I/O</h4>
<a name="index-console-i_002fo-as-part-of-file_002di_002fo"></a>

<p>By default and if not explicitly closed by the target system, the file
descriptors 0, 1 and 2 are connected to the <small>GDB</small> console.  Output
on the <small>GDB</small> console is handled as any other file output operation
(<code>write(1, &hellip;)</code> or <code>write(2, &hellip;)</code>).  Console input is handled
by <small>GDB</small> so that after the target read request from file descriptor
0 all following typing is buffered until either one of the following
conditions is met:
</p>
<ul>
<li> The user types <kbd>Ctrl-c</kbd>.  The behaviour is as explained above, and the
<code>read</code>
system call is treated as finished.

</li><li> The user presses <tt class="key">RET</tt>.  This is treated as end of input with a trailing
newline.

</li><li> The user types <kbd>Ctrl-d</kbd>.  This is treated as end of input.  No trailing
character (neither newline nor &lsquo;<samp>Ctrl-D</samp>&rsquo;) is appended to the input.

</li></ul>

<p>If the user has typed more characters than fit in the buffer given to
the <code>read</code> call, the trailing characters are buffered in <small>GDB</small> until
either another <code>read(0, &hellip;)</code> is requested by the target, or debugging
is stopped at the user&rsquo;s request.
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