...
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="3d67eda634ff1f2a-860182fb-49364e61-b17591d7-27999a7bcbdb1e7b3cd32efd"><ac:plain-text-body><![CDATA[
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[
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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)