Index: src/os_unix.c
==================================================================
--- src/os_unix.c
+++ src/os_unix.c
@@ -2393,11 +2393,11 @@
   if( isExclusive ) oflags |= (O_EXCL|O_NOFOLLOW);
   oflags |= (O_LARGEFILE|O_BINARY);
 
   memset(pFile, 0, sizeof(unixFile));
   fd = open(zPath, oflags, isDelete?0600:SQLITE_DEFAULT_FILE_PERMISSIONS);
-  if( fd<0 && isReadWrite && !isExclusive ){
+  if( fd<0 && errno!=EISDIR && isReadWrite && !isExclusive ){
     /* Failed to open the file for read/write access. Try read-only. */
     flags &= ~(SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE);
     flags |= SQLITE_OPEN_READONLY;
     return unixOpen(pVfs, zPath, pFile, flags, pOutFlags);
   }