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17<title>Debugging with GDB: Byte Order</title>
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64<a name="Byte-Order"></a>
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66<p>
67Previous: <a href="Target-Commands.html#Target-Commands" accesskey="p" rel="previous">Target Commands</a>, Up: <a href="Targets.html#Targets" accesskey="u" rel="up">Targets</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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70<a name="Choosing-Target-Byte-Order"></a>
71<h3 class="section">19.3 Choosing Target Byte Order</h3>
72
73<a name="index-choosing-target-byte-order"></a>
74<a name="index-target-byte-order"></a>
75
76<p>Some types of processors, such as the <acronym>MIPS</acronym>, PowerPC, and Renesas SH,
77offer the ability to run either big-endian or little-endian byte
78orders.  Usually the executable or symbol will include a bit to
79designate the endian-ness, and you will not need to worry about
80which to use.  However, you may still find it useful to adjust
81<small>GDB</small>&rsquo;s idea of processor endian-ness manually.
82</p>
83<dl compact="compact">
84<dd><a name="index-set-endian"></a>
85</dd>
86<dt><code>set endian big</code></dt>
87<dd><p>Instruct <small>GDB</small> to assume the target is big-endian.
88</p>
89</dd>
90<dt><code>set endian little</code></dt>
91<dd><p>Instruct <small>GDB</small> to assume the target is little-endian.
92</p>
93</dd>
94<dt><code>set endian auto</code></dt>
95<dd><p>Instruct <small>GDB</small> to use the byte order associated with the
96executable.
97</p>
98</dd>
99<dt><code>show endian</code></dt>
100<dd><p>Display <small>GDB</small>&rsquo;s current idea of the target byte order.
101</p>
102</dd>
103</dl>
104
105<p>If the <code>set endian auto</code> mode is in effect and no executable has
106been selected, then the endianness used is the last one chosen either
107by one of the <code>set endian big</code> and <code>set endian little</code>
108commands or by inferring from the last executable used.  If no
109endianness has been previously chosen, then the default for this mode
110is inferred from the target <small>GDB</small> has been built for, and is
111<code>little</code> if the name of the target CPU has an <code>el</code> suffix
112and <code>big</code> otherwise.
113</p>
114<p>Note that these commands merely adjust interpretation of symbolic
115data on the host, and that they have absolutely no effect on the
116target system.
117</p>
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