Actually seek when necessary.
diff --git a/lib/zip_source_win32handle.c b/lib/zip_source_win32handle.c
index 256d997..3a6b9a0 100644
--- a/lib/zip_source_win32handle.c
+++ b/lib/zip_source_win32handle.c
@@ -338,7 +338,7 @@
 	if (args == NULL)
 	    return -1;
 
-	need_seek = ctx->closep;
+	need_seek = 1;
 
 	switch (args->whence) {
 	case SEEK_SET: