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<a name="Format-Commands"></a>
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<p>
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Next: <a href="REGION_005fALIAS.html#REGION_005fALIAS" accesskey="n" rel="next">REGION_ALIAS</a>, Previous: <a href="File-Commands.html#File-Commands" accesskey="p" rel="previous">File Commands</a>, Up: <a href="Simple-Commands.html#Simple-Commands" accesskey="u" rel="up">Simple Commands</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="LD-Index.html#LD-Index" title="Index" rel="index">Index</a>]</p>
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<hr>
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<a name="Commands-Dealing-with-Object-File-Formats"></a>
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<h4 class="subsection">3.4.3 Commands Dealing with Object File Formats</h4>
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<p>A couple of linker script commands deal with object file formats.
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</p>
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<dl compact="compact">
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<dt><code>OUTPUT_FORMAT(<var>bfdname</var>)</code></dt>
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<dt><code>OUTPUT_FORMAT(<var>default</var>, <var>big</var>, <var>little</var>)</code></dt>
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<dd><a name="index-OUTPUT_005fFORMAT_0028bfdname_0029"></a>
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<a name="index-output-file-format-in-linker-script"></a>
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<p>The <code>OUTPUT_FORMAT</code> command names the BFD format to use for the
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output file (see <a href="BFD.html#BFD">BFD</a>). Using <code>OUTPUT_FORMAT(<var>bfdname</var>)</code> is
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exactly like using ‘<samp>--oformat <var>bfdname</var></samp>’ on the command line
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(see <a href="Options.html#Options">Command-line Options</a>). If both are used, the command
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line option takes precedence.
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</p>
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<p>You can use <code>OUTPUT_FORMAT</code> with three arguments to use different
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formats based on the ‘<samp>-EB</samp>’ and ‘<samp>-EL</samp>’ command-line options.
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This permits the linker script to set the output format based on the
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desired endianness.
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</p>
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<p>If neither ‘<samp>-EB</samp>’ nor ‘<samp>-EL</samp>’ are used, then the output format
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will be the first argument, <var>default</var>. If ‘<samp>-EB</samp>’ is used, the
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output format will be the second argument, <var>big</var>. If ‘<samp>-EL</samp>’ is
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used, the output format will be the third argument, <var>little</var>.
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</p>
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<p>For example, the default linker script for the MIPS ELF target uses this
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command:
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</p><div class="smallexample">
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<pre class="smallexample">OUTPUT_FORMAT(elf32-bigmips, elf32-bigmips, elf32-littlemips)
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</pre></div>
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<p>This says that the default format for the output file is
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‘<samp>elf32-bigmips</samp>’, but if the user uses the ‘<samp>-EL</samp>’ command-line
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option, the output file will be created in the ‘<samp>elf32-littlemips</samp>’
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format.
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</p>
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</dd>
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<dt><code>TARGET(<var>bfdname</var>)</code></dt>
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<dd><a name="index-TARGET_0028bfdname_0029"></a>
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<a name="index-input-file-format-in-linker-script"></a>
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<p>The <code>TARGET</code> command names the BFD format to use when reading input
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files. It affects subsequent <code>INPUT</code> and <code>GROUP</code> commands.
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This command is like using ‘<samp>-b <var>bfdname</var></samp>’ on the command line
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(see <a href="Options.html#Options">Command-line Options</a>). If the <code>TARGET</code> command
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is used but <code>OUTPUT_FORMAT</code> is not, then the last <code>TARGET</code>
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command is also used to set the format for the output file. See <a href="BFD.html#BFD">BFD</a>.
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</p></dd>
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Next: <a href="REGION_005fALIAS.html#REGION_005fALIAS" accesskey="n" rel="next">REGION_ALIAS</a>, Previous: <a href="File-Commands.html#File-Commands" accesskey="p" rel="previous">File Commands</a>, Up: <a href="Simple-Commands.html#Simple-Commands" accesskey="u" rel="up">Simple Commands</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="LD-Index.html#LD-Index" title="Index" rel="index">Index</a>]</p>
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