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The following non-compliant code creates some_file in the /tmp directory. The name is hard - coded and is thus not unique or unpredictable.
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For Microsoft Visual Studio 2005, the name generated by tmpnam_s consists of a program-generated filename and, after the first call to tmpnam_s(), a file extension of sequential numbers in base 32 (.1-.1vvvvvu, when TMP_MAX_S in stdio.h is INT_MAX).
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The mktemp() function was marked LEGACY in the Open Group Base Specifications Issue 6.
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For glibc versions 2.0.6 and earlier, the file is created with permissions 0666; for glibc versions 2.0.7 and later, the file is created with permissions 0600. On NetBSD, the file is created with permissions 0600.
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