I spent a few minutes in sb-posix\interface.lisp in SBCL and found that fork was defined under:
#-win32
Which apparently means it's not part of the win32 version. Bummer...
I'll post if I come up with a valid workaround.
Thanks again! (by the way, the wart's code is a joy to read and makes it simple to troubleshoot)
Feel free to ping me by email as well (address in profile).
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