Index: src/test4.c
==================================================================
--- src/test4.c
+++ src/test4.c
@@ -11,11 +11,11 @@
 *************************************************************************
 ** Code for testing the the SQLite library in a multithreaded environment.
 */
 #include "sqliteInt.h"
 #include "tcl.h"
-#if defined(SQLITE_OS_UNIX) && OS_UNIX==1 && SQLITE_THREADSAFE
+#if SQLITE_OS_UNIX && SQLITE_THREADSAFE
 #include <stdlib.h>
 #include <string.h>
 #include <pthread.h>
 #include <sched.h>
 #include <ctype.h>

Index: src/test7.c
==================================================================
--- src/test7.c
+++ src/test7.c
@@ -18,11 +18,11 @@
 /*
 ** This test only works on UNIX with a SQLITE_THREADSAFE build that includes
 ** the SQLITE_SERVER option.
 */
 #if defined(SQLITE_SERVER) && !defined(SQLITE_OMIT_SHARED_CACHE) && \
-    defined(SQLITE_OS_UNIX) && OS_UNIX && SQLITE_THREADSAFE
+    SQLITE_OS_UNIX && SQLITE_THREADSAFE
 
 #include <stdlib.h>
 #include <string.h>
 #include <pthread.h>
 #include <sched.h>

Index: src/test_demovfs.c
==================================================================
--- src/test_demovfs.c
+++ src/test_demovfs.c
@@ -113,11 +113,11 @@
 **
 **   Much more efficient if the underlying OS is not caching write 
 **   operations.
 */
 
-#if !defined(SQLITE_TEST) || defined(SQLITE_OS_UNIX)
+#if !defined(SQLITE_TEST) || SQLITE_OS_UNIX
 
 #include <sqlite3.h>
 
 #include <assert.h>
 #include <string.h>
@@ -635,18 +635,18 @@
     demoCurrentTime,              /* xCurrentTime */
   };
   return &demovfs;
 }
 
-#endif /* !defined(SQLITE_TEST) || defined(SQLITE_OS_UNIX) */
+#endif /* !defined(SQLITE_TEST) || SQLITE_OS_UNIX */
 
 
 #ifdef SQLITE_TEST
 
 #include <tcl.h>
 
-#ifdef SQLITE_OS_UNIX
+#if SQLITE_OS_UNIX
 static int register_demovfs(
   ClientData clientData, /* Pointer to sqlite3_enable_XXX function */
   Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
   int objc,              /* Number of arguments */
   Tcl_Obj *CONST objv[]  /* Command arguments */

Index: src/test_osinst.c
==================================================================
--- src/test_osinst.c
+++ src/test_osinst.c
@@ -211,18 +211,18 @@
   vfslogShmLock,                  /* xShmLock */
   vfslogShmBarrier,               /* xShmBarrier */
   vfslogShmUnmap                  /* xShmUnmap */
 };
 
-#if defined(SQLITE_OS_UNIX) && !defined(NO_GETTOD)
+#if SQLITE_OS_UNIX && !defined(NO_GETTOD)
 #include <sys/time.h>
 static sqlite3_uint64 vfslog_time(){
   struct timeval sTime;
   gettimeofday(&sTime, 0);
   return sTime.tv_usec + (sqlite3_uint64)sTime.tv_sec * 1000000;
 }
-#elif defined(SQLITE_OS_WIN)
+#elif SQLITE_OS_WIN
 #include <windows.h>
 #include <time.h>
 static sqlite3_uint64 vfslog_time(){
   FILETIME ft;
   sqlite3_uint64 u64time = 0;

Index: src/test_server.c
==================================================================
--- src/test_server.c
+++ src/test_server.c
@@ -204,11 +204,11 @@
 /*
 ** Only compile the code in this file on UNIX with a SQLITE_THREADSAFE build
 ** and only if the SQLITE_SERVER macro is defined.
 */
 #if defined(SQLITE_SERVER) && !defined(SQLITE_OMIT_SHARED_CACHE)
-#if defined(SQLITE_OS_UNIX) && OS_UNIX && SQLITE_THREADSAFE
+#if SQLITE_OS_UNIX && SQLITE_THREADSAFE
 
 /*
 ** We require only pthreads and the public interface of SQLite.
 */
 #include <pthread.h>
@@ -485,7 +485,7 @@
   pthread_cond_broadcast(&g.serverWakeup);
   pthread_mutex_lock(&g.serverMutex);
   pthread_mutex_unlock(&g.serverMutex);
 }
 
-#endif /* defined(SQLITE_OS_UNIX) && OS_UNIX && SQLITE_THREADSAFE */
+#endif /* SQLITE_OS_UNIX && SQLITE_THREADSAFE */
 #endif /* defined(SQLITE_SERVER) */

Index: src/test_syscall.c
==================================================================
--- src/test_syscall.c
+++ src/test_syscall.c
@@ -74,11 +74,11 @@
 #include <stdlib.h>
 #include <string.h>
 #include <assert.h>
 
 #include "sqliteInt.h"
-#ifdef SQLITE_OS_UNIX
+#if SQLITE_OS_UNIX
 
 /* From test1.c */
 extern const char *sqlite3TestErrorName(int);
 
 #include <sys/types.h>

Index: src/test_thread.c
==================================================================
--- src/test_thread.c
+++ src/test_thread.c
@@ -51,11 +51,11 @@
   Tcl_Interp *interp;      /* The interpreter to execute it in. */
 };
 
 static Tcl_ObjCmdProc sqlthread_proc;
 static Tcl_ObjCmdProc clock_seconds_proc;
-#if defined(SQLITE_OS_UNIX) && defined(SQLITE_ENABLE_UNLOCK_NOTIFY)
+#if SQLITE_OS_UNIX && defined(SQLITE_ENABLE_UNLOCK_NOTIFY)
 static Tcl_ObjCmdProc blocking_step_proc;
 static Tcl_ObjCmdProc blocking_prepare_v2_proc;
 #endif
 int Sqlitetest1_Init(Tcl_Interp *);
 int Sqlite3_Init(Tcl_Interp *);
@@ -114,11 +114,11 @@
   extern int Sqlitetest_mutex_Init(Tcl_Interp*);
 
   interp = Tcl_CreateInterp();
   Tcl_CreateObjCommand(interp, "clock_seconds", clock_seconds_proc, 0, 0);
   Tcl_CreateObjCommand(interp, "sqlthread", sqlthread_proc, pSqlThread, 0);
-#if defined(SQLITE_OS_UNIX) && defined(SQLITE_ENABLE_UNLOCK_NOTIFY)
+#if SQLITE_OS_UNIX && defined(SQLITE_ENABLE_UNLOCK_NOTIFY)
   Tcl_CreateObjCommand(interp, "sqlite3_blocking_step", blocking_step_proc,0,0);
   Tcl_CreateObjCommand(interp, 
       "sqlite3_blocking_prepare_v2", blocking_prepare_v2_proc, (void *)1, 0);
   Tcl_CreateObjCommand(interp, 
       "sqlite3_nonblocking_prepare_v2", blocking_prepare_v2_proc, 0, 0);
@@ -390,11 +390,11 @@
 ** automatically extracted from this file and used as part of the
 ** documentation for the sqlite3_unlock_notify() API function. This
 ** should be considered if these functions are to be extended (i.e. to 
 ** support windows) in the future.
 */ 
-#if defined(SQLITE_OS_UNIX) && defined(SQLITE_ENABLE_UNLOCK_NOTIFY)
+#if SQLITE_OS_UNIX && defined(SQLITE_ENABLE_UNLOCK_NOTIFY)
 
 /* BEGIN_SQLITE_BLOCKING_STEP */
 /* This example uses the pthreads API */
 #include <pthread.h>
 
@@ -612,11 +612,11 @@
 ** Register commands with the TCL interpreter.
 */
 int SqlitetestThread_Init(Tcl_Interp *interp){
   Tcl_CreateObjCommand(interp, "sqlthread", sqlthread_proc, 0, 0);
   Tcl_CreateObjCommand(interp, "clock_seconds", clock_seconds_proc, 0, 0);
-#if defined(SQLITE_OS_UNIX) && defined(SQLITE_ENABLE_UNLOCK_NOTIFY)
+#if SQLITE_OS_UNIX && defined(SQLITE_ENABLE_UNLOCK_NOTIFY)
   Tcl_CreateObjCommand(interp, "sqlite3_blocking_step", blocking_step_proc,0,0);
   Tcl_CreateObjCommand(interp, 
       "sqlite3_blocking_prepare_v2", blocking_prepare_v2_proc, (void *)1, 0);
   Tcl_CreateObjCommand(interp, 
       "sqlite3_nonblocking_prepare_v2", blocking_prepare_v2_proc, 0, 0);

Index: test/releasetest.tcl
==================================================================
--- test/releasetest.tcl
+++ test/releasetest.tcl
@@ -62,11 +62,10 @@
   }
   "Unlock-Notify" {
     -O2
     -DSQLITE_ENABLE_UNLOCK_NOTIFY
     -DSQLITE_THREADSAFE
-    -DOS_UNIX
     -DSQLITE_TCL_DEFAULT_FULLMUTEX=1
   }
   "Secure-Delete" {
     -O2
     -DSQLITE_SECURE_DELETE=1