Improve documentation about differences between ledger 2.6 and ledger…

… 3.0.

GnuCash support removed, environment variables deprecated.

doc/ledger3.texi

@@ -9086,15 +9086,40 @@ for example, issue @samp{ctest -V -R "5FB"}.
 @node Major Changes from version 2.6, Example Journal File, Ledger for Developers, Top
 @chapter Major Changes from version 2.6
 
+The following have been removed from Ledger 3.0:
+
 @itemize
 
 @item
-OFX support has been removed from Ledger 3.0
+OFX support
 
 @item
+GnuCash file import
+
+@end itemize
+
+@noindent
+The following are deprecated in Ledger 3.0:
+
+@itemize
+
+@item 
 Single character value expressions are deprecated and should be changed
 to the new value expressions available in 3.0
 
+@item
+The following environment variables have been renamed in Ledger 3.0:
+@table @env
+@item LEDGER
+is now @env{LEDGER_FILE},
+@item LEDGER_INIT
+is now @env{LEDGER_INIT_FILE},
+@item PRICE_HIST
+is now @env{LEDGER_PRICE_DB},
+@item PRICE_EXP
+is now @env{LEDGER_PRICE_EXP}.
+@end table
+
 @end itemize
 
 @node  Example Journal File, Miscellaneous Notes, Major Changes from version 2.6, Top

src/global.cc

@@ -399,11 +399,13 @@ void global_scope_t::read_environment_settings(char * envp[])
       process_option("environ", "init-file", report(), p, "LEDGER_INIT");
   }
   if (const char * p = std::getenv("PRICE_HIST")) {
-    if (! std::getenv("LEDGER_PRICEDB"))
+    if (! std::getenv("LEDGER_PRICE_DB"))
       process_option("environ", "price-db", report(), p, "PRICE_HIST");
   }
-  if (const char * p = std::getenv("PRICE_EXP"))
-    process_option("environ", "price-exp", report(), p, "PRICE_EXP");
+  if (const char * p = std::getenv("PRICE_EXP")) {
+    if (! std::getenv("LEDGER_PRICE_EXP"))
+			process_option("environ", "price-exp", report(), p, "PRICE_EXP");
+	}
 #endif
 
   TRACE_FINISH(environment, 1);