...
All occurrences in a source file of the following sequences of three characters (that is, trigraph sequences) are replaced with the corresponding single character.
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#
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]
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|
<ac:structured-macro ac:name="unmigrated-wiki-markup" ac:schema-version="1" ac:macro-id="5febf907239fe3ac-8c5fdb48-47a84447-b7149324-8737ad02e91f8bcbccff53e8"><ac:plain-text-body><![CDATA[
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[
??'
^
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}
]]></ac:plain-text-body></ac:structured-macro>
??/
\
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{
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~
...
PRE06-C. Enclose header files in an inclusion guard - CERT Secure Coding Standards 01. Preprocessor (PRE)