> First, we can make a thread-safe implementation, like Illumos/Solaris. This has some limitations: it leaks memory in setenv(), and is still unsafe if a progra

> First, we can make a thread-safe implementation, like Illumos/Solaris. This has some limitations: it leaks memory in setenv(), and is still unsafe if a program uses putenv() or the environ variable. No, `putenv()` in Solaris/Illumos is thread-safe too. And the program should NOT write to `environ`, but as it happens Solaris/Illumos allows that too (but it can cause a lock to be taken in `getenv()`. > Add a function to copy one single environment variable to a user-specified buffer, similar to getenv_s(). Because Windows has one? Fine, but adding a version that allocates the copy would be more convenient. BTW, HN is having problems that are leading to dup comments. I get "We're having some trouble serving your request. Sorry!", but the action happens anyways.