From 1f88a38e2e1f03951160491ea75364f39fec1286 Mon Sep 17 00:00:00 2001
From: Stephen Heumann <stephenheumann@gmail.com>
Date: Mon, 27 Jun 2022 17:59:21 -0500
Subject: [PATCH] Clear the EOF flag on successful calls to ungetc().

This is specified by the C standards.
---
 stdio.asm | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/stdio.asm b/stdio.asm
index 6f81bbf..6fe66b5 100644
--- a/stdio.asm
+++ b/stdio.asm
@@ -3194,8 +3194,11 @@ char     equ   1                        character to return
          and   #$00FF
          sta   [stream],Y
          sta   char
-rts      long  M
-         creturn 2:char
+         ldy   #FILE_flag               clear the EOF flag
+         lda   [stream],Y
+         and   #$FFFF-_IOEOF
+         sta   [stream],Y
+rts      creturn 2:char
          end
 
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