diff -ur mtools-3.9.9/plain_io.c mtools-3.9.9-pi/plain_io.c
--- mtools-3.9.9/plain_io.c	2003-02-16 17:18:58.000000000 +0100
+++ mtools-3.9.9-pi/plain_io.c	2003-10-24 15:25:53.000000000 +0200
@@ -524,6 +524,7 @@
 		printOom();
 		return 0;
 	}
+    memset((void*)This, 0, sizeof(SimpleFile_t));
 	This->scsi_sector_size = 512;
 	This->seekable = 1;
 #ifdef OS_hpux