From a09ceabd05a4121b745995e1abbb9a4c5b407414 Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Tue, 25 Jan 2011 15:24:46 +0000
Subject: [PATCH] notes: commodids are offsets

---
 yarrg/notes | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/yarrg/notes b/yarrg/notes
index 99438d9..8895c71 100644
--- a/yarrg/notes
+++ b/yarrg/notes
@@ -73,11 +73,19 @@ format is a series of lines
  auxil	<stallid>=:<stallname>
  auxil	<metadataid>=&<metadatalenbytes>\n<metadata>
 
- log/old <metadataid>&<timestamp>		applies to following data
- log/old [<stallid>:]<commodid>					delete offer
- log/old [<stallid>:]<commodid>@<newprice>			adjust price
- log/old [<stallid>:]<commodid>[@<newprice>]-<qtyreduced>	adjust qty
- log/old [<stallid>:]<commodid>[@<newprice>]+<qtyincreased>	maybe price
+ log/old <metadataid>&<timestamp>
+	applies to following data
+
+ log/old [<stallid>:]<commodiddelta>				 delete offer
+ log/old [<stallid>:]<commodiddelta>@<newprice>			 adjust price
+ log/old [<stallid>:]<commodiddelta>[@<newprice>]-<qtyreduced>	 adjust qty
+ log/old [<stallid>:]<commodiddelta>[@<newprice>]+<qtyincreased>  maybe price
+	In each case commodiddelta is the number to add to
+	the previous commodid to get the new one; or for a new
+	stallid, the actual commodid (starting from zero).
+	-ve numbers cannot be represented so they have to be in
+	order.
+
  log	 ^<uploadlenbytes-padded-to-4-base62-digits>
 			applies to previous data
 			includes 6-byte len of one ^... line
-- 
2.30.2