message: core: unistd is not available on Windows
diff: #include <gtest/gtest.h>
  -#include <unistd.h>
  #include "fs.h"
  #if !defined(WINDOWS)
  #define PATH_MAX 4096
  +#include <unistd.h>
  +
  TEST(Filesystem, AbsolutePathUnchanged)
  {
  const std::string path = "/sbin/init";
  