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<h4 class="subsection">3.4.3 Commands Dealing with Object File Formats</h4>

<p>A couple of linker script commands deal with object file formats.

     <dl>
<dt><code>OUTPUT_FORMAT(</code><var>bfdname</var><code>)</code><dt><code>OUTPUT_FORMAT(</code><var>default</var><code>, </code><var>big</var><code>, </code><var>little</var><code>)</code><dd><a name="index-OUTPUT_005fFORMAT_0028_0040var_007bbfdname_007d_0029-415"></a><a name="index-output-file-format-in-linker-script-416"></a>The <code>OUTPUT_FORMAT</code> command names the BFD format to use for the
output file (see <a href="BFD.html#BFD">BFD</a>).  Using <code>OUTPUT_FORMAT(</code><var>bfdname</var><code>)</code> is
exactly like using &lsquo;<samp><span class="samp">--oformat </span><var>bfdname</var></samp>&rsquo; on the command line
(see <a href="Options.html#Options">Command-line Options</a>).  If both are used, the command
line option takes precedence.

     <p>You can use <code>OUTPUT_FORMAT</code> with three arguments to use different
formats based on the &lsquo;<samp><span class="samp">-EB</span></samp>&rsquo; and &lsquo;<samp><span class="samp">-EL</span></samp>&rsquo; command-line options. 
This permits the linker script to set the output format based on the
desired endianness.

     <p>If neither &lsquo;<samp><span class="samp">-EB</span></samp>&rsquo; nor &lsquo;<samp><span class="samp">-EL</span></samp>&rsquo; are used, then the output format
will be the first argument, <var>default</var>.  If &lsquo;<samp><span class="samp">-EB</span></samp>&rsquo; is used, the
output format will be the second argument, <var>big</var>.  If &lsquo;<samp><span class="samp">-EL</span></samp>&rsquo; is
used, the output format will be the third argument, <var>little</var>.

     <p>For example, the default linker script for the MIPS ELF target uses this
command:
     <pre class="smallexample">          OUTPUT_FORMAT(elf32-bigmips, elf32-bigmips, elf32-littlemips)
</pre>
     <p>This says that the default format for the output file is
&lsquo;<samp><span class="samp">elf32-bigmips</span></samp>&rsquo;, but if the user uses the &lsquo;<samp><span class="samp">-EL</span></samp>&rsquo; command-line
option, the output file will be created in the &lsquo;<samp><span class="samp">elf32-littlemips</span></samp>&rsquo;
format.

     <br><dt><code>TARGET(</code><var>bfdname</var><code>)</code><dd><a name="index-TARGET_0028_0040var_007bbfdname_007d_0029-417"></a><a name="index-input-file-format-in-linker-script-418"></a>The <code>TARGET</code> command names the BFD format to use when reading input
files.  It affects subsequent <code>INPUT</code> and <code>GROUP</code> commands. 
This command is like using &lsquo;<samp><span class="samp">-b </span><var>bfdname</var></samp>&rsquo; on the command line
(see <a href="Options.html#Options">Command-line Options</a>).  If the <code>TARGET</code> command
is used but <code>OUTPUT_FORMAT</code> is not, then the last <code>TARGET</code>
command is also used to set the format for the output file.  See <a href="BFD.html#BFD">BFD</a>. 
</dl>

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