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ISO/IEC 9899:2011 Section 7.11.1.1, "The setlocale function," Section 7.11.2.1, "The localeconv function," Section 7.22.4.6, "The getenv function," and Section 7.24.6.2, "The strerror function"
ISO/IEC TR TS 17961 (Draft) Modifying the string returned by getenv, localeconv, setlocale, and strerror [libmod]
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