From 08431c0924e5d66212ffc7e65a2c12f8673d24ac Mon Sep 17 00:00:00 2001
From: Wolfgang Thaller <wolfgang.thaller@gmx.net>
Date: Sun, 22 Sep 2019 23:22:30 +0200
Subject: [PATCH] FSRead and FSWrite need to pass ioPosMode = fsAtMark

---
 custom/glue.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/custom/glue.c b/custom/glue.c
index 6294d07..c81e247 100644
--- a/custom/glue.c
+++ b/custom/glue.c
@@ -268,6 +268,7 @@ pascal OSErr FSRead(short refNum, long *count, void *buffPtr)
     pb.ioParam.ioRefNum = refNum;
     pb.ioParam.ioBuffer = buffPtr;
     pb.ioParam.ioReqCount = *count;
+    pb.ioParam.ioPosMode = fsAtMark;
 
     err = PBReadSync(&pb);
     *count = pb.ioParam.ioActCount;
@@ -281,6 +282,7 @@ pascal OSErr FSWrite(short refNum, long *count, const void *buffPtr)
     pb.ioParam.ioRefNum = refNum;
     pb.ioParam.ioBuffer = (void *)buffPtr;
     pb.ioParam.ioReqCount = *count;
+    pb.ioParam.ioPosMode = fsAtMark;
 
     err = PBWriteSync(&pb);
     *count = pb.ioParam.ioActCount;