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<h3 class="section">17.8 Pseudo-Terminals</h3>

<p><a name="index-pseudo_002dterminals-2023"></a>
A <dfn>pseudo-terminal</dfn> is a special interprocess communication channel
that acts like a terminal.  One end of the channel is called the
<dfn>master</dfn> side or <dfn>master pseudo-terminal device</dfn>, the other side
is called the <dfn>slave</dfn> side.  Data written to the master side is
received by the slave side as if it was the result of a user typing at
an ordinary terminal, and data written to the slave side is sent to the
master side as if it was written on an ordinary terminal.

   <p>Pseudo terminals are the way programs like <code>xterm</code> and <code>emacs</code>
implement their terminal emulation functionality.

<ul class="menu">
<li><a accesskey="1" href="Allocation.html#Allocation">Allocation</a>:              Allocating a pseudo terminal. 
<li><a accesskey="2" href="Pseudo_002dTerminal-Pairs.html#Pseudo_002dTerminal-Pairs">Pseudo-Terminal Pairs</a>:   How to open both sides of a
                            pseudo-terminal in a single operation. 
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