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After the loop ends, path is modified as follows: "/usr/bin\0/bin\0/usr/sbin\0/sbin\0". This is an issue because the local path variable becomes /usr/bin and because the environment variable PATH has been unintentionally changed, which can have unintended consequences (see ENV30-C. Do not modify the string returned by getenv()).
Compliant Solution
In this solution the string being tokenized is copied into a temporary buffer which is not referenced after the calls to strtok():
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