https://bugs.winehq.org/show_bug.cgi?id=55835
--- Comment #4 from blitzkriegoutlaw@hotmail.com --- It is internal software so not publicly available. I can't state what it is.
The unix man page for getenv states: The implementation of getenv() is not required to be reentrant. The string pointed to by the return value of getenv() may be statically allocated, and can be modified by a subsequent call to getenv(), putenv(3), setenv(3), or unsetenv(3).
The Microsoft help page has no such note. However, that part of the code compiles and runs on Windows and Linux and I don't have this problem. That unix note probably doesn't apply to Linux as haven't seen the problem there. It wasn't until I tried to run our legacy HMI in Wine that I ran into this problem. Since I have the source code, it wasn't hard to work around the issue by copying the result of getenv into an character array. I believe it is a bug since Windows getenv is reentrant.