   fatalError("realpath is unimplemented")
 }
 
+private func __randname(_ buffer: UnsafeMutablePointer<CChar>) {
+  let alpha = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+  _ = (0 ..< 6).map { index in
+      buffer[index] = CChar(alpha.shuffled().randomElement()!.utf8.first!)
+  }
+}
+
 // char *mkdtemp(char *template);
 // NOTE(compnerd) this is unsafe!  This assumes that the template is *ASCII*.
 public func mkdtemp(

    _ template: UnsafeMutablePointer<CChar>?,
    _ suffixlen: Int32
) -> Int32 {
  guard let template = template else { return -EINVAL }
  return String(cString: template).withCString(encodedAs: UTF16.self) {
    let capacity: Int = wcslen($0) + 1
    return $0.withMemoryRebound(to: wchar_t.self, capacity: capacity) {
      guard _wmktemp_s(UnsafeMutablePointer(mutating: $0), capacity) == 0 else {
        return -EINVAL
      }

      var fd: Int32 = -1
      _wsopen_s(&fd, $0, _O_RDWR | _O_CREAT | _O_BINARY | _O_NOINHERIT,
                _SH_DENYNO, _S_IREAD | _S_IWRITE)

      String(decodingCString: $0, as: UTF16.self).utf8CString.withUnsafeBytes {
        template.assign(from: $0.bindMemory(to: CChar.self).baseAddress!,
                        count: $0.count)
      }
      return fd
    }
  }
}
#endif

    return nil
  }

  // Attempt to create the directory
  var retries: Int = 100
  repeat {
    __randname(template + length - 6)
    if _mkdir(template) == 0 {
      return template
    }
