From feb621e000658f60be28d38a1d4dd3e9c55a124b Mon Sep 17 00:00:00 2001
From: Todd Jeffreys <todd@voidpointer.org>
Date: Mon, 12 Apr 2021 20:57:11 -0600
Subject: [PATCH] Make Int 7Bh queries return KeyValueNotFound when necessary.

Queries that specify a key are searchin by key and KeyValueNotFound is a
better error than EOF. EOF is still used for queries that are
"key-less", such as Next/Previous. Those queries should return EOF.
---
 MBBSEmu/DOS/Interrupts/Int7Bh.cs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/MBBSEmu/DOS/Interrupts/Int7Bh.cs b/MBBSEmu/DOS/Interrupts/Int7Bh.cs
index 9dfa4a23..3ad2afc5 100644
--- a/MBBSEmu/DOS/Interrupts/Int7Bh.cs
+++ b/MBBSEmu/DOS/Interrupts/Int7Bh.cs
@@ -24,7 +24,7 @@ public enum BtrieveError
         InvalidKeyNumber = 6,
         DifferentKeyNumber = 7,
         InvalidPositioning = 8,
-        EOF = 9 ,
+        EOF = 9,
         NonModifiableKeyValue = 10,
         InvalidFileName = 11,
         FileNotFound = 12,
@@ -418,7 +418,7 @@ private BtrieveError Query(BtrieveCommand command)
                 key = _memory.GetArray(command.key_buffer_segment, command.key_buffer_offset, command.key_buffer_length);
 
             if (!db.PerformOperation(command.key_number, key, command.operation))
-                return BtrieveError.EOF;
+                return command.operation.RequiresKey() ? BtrieveError.KeyValueNotFound : BtrieveError.EOF;
 
             var data = db.GetRecord();