diff --git a/direct/src/plugin/find_root_dir.cxx b/direct/src/plugin/find_root_dir.cxx
index cbe3973177..b7c955a222 100755
--- a/direct/src/plugin/find_root_dir.cxx
+++ b/direct/src/plugin/find_root_dir.cxx
@@ -25,12 +25,14 @@
 #include <sys/stat.h>
 #endif
 
+#ifdef _WIN32
 // From KnownFolders.h (part of Vista SDK):
 #define DEFINE_KNOWN_FOLDER(name, l, w1, w2, b1, b2, b3, b4, b5, b6, b7, b8) \
    const GUID name = { l, w1, w2, { b1, b2,  b3,  b4,  b5,  b6,  b7,  b8 } }
 DEFINE_KNOWN_FOLDER(FOLDERID_LocalAppData, 0xF1B32785, 0x6FBA, 0x4FCF, 0x9D, 0x55, 0x7B, 0x8E, 0x7F, 0x15, 0x70, 0x91);
 DEFINE_KNOWN_FOLDER(FOLDERID_LocalAppDataLow, 0xA520A1A4, 0x1780, 0x4FF6, 0xBD, 0x18, 0x16, 0x73, 0x43, 0xC5, 0xAF, 0x16);
 DEFINE_KNOWN_FOLDER(FOLDERID_InternetCache, 0x352481E8, 0x33BE, 0x4251, 0xBA, 0x85, 0x60, 0x07, 0xCA, 0xED, 0xCF, 0x9D); 
+#endif  // _WIN32
 
 
 #ifdef _WIN32