Fix for HISTCMD when HISTFILE is defined, but HISTSIZE is not

[Geoff Odhner]

Configuration Information [Automatically generated, do not change]:
Machine: i686
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS:  -DPROGRAM='bash' -DCONF_HOSTTYPE='i686' 
-DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='i686-pc-linux-gnu' 
-DCONF_VENDOR='pc' -DLOCALEDIR='/home/geoff/i686/share/locale' -DPACKAGE='bash' 
-DSHELL -DHAVE_CONFIG_H  -I.  -I.. -I../include -I../lib   -g -O2
uname output: Linux monster 2.6.9-11.ELsmp #1 SMP Fri May 20 18:26:27 EDT 2005 
i686 i686 i386 GNU/Linux
Machine Type: i686-pc-linux-gnu

Bash Version: 3.0
Patch Level: 16
Release Status: release

Description:
        Unsetting HISTSIZE allows an unlimited number of entries in the 
        history, but it unfortunately causes $HISTCMD to evaluate as 1.
        This should only happen if HISTFILE is unset.

Repeat-By:
        execute the following two command lines:

        % unset HISTSIZE
        % echo HISTCMD=$HISTCMD
        HISTCMD=1
        % 

Fix:
        The following patch corrects the problem, making HISTCMD
        available whenever there is a history file:

======================================================================
diff -Naur bash-3.0/bashhist.c bash-3.0-fixed/bashhist.c
--- bash-3.0/bashhist.c       2004-03-22 08:27:59.000000000 -0500
+++ bash-3.0-fixed/bashhist.c 2005-09-29 09:53:19.903722088 -0400
@@ -706,7 +706,7 @@
 history_number ()
 {
   using_history ();
-  return (get_string_value ("HISTSIZE") ? history_base + where_history () : 1);
+  return (get_string_value ("HISTFILE") ? history_base + where_history () : 1);
 }
 
 static int
======================================================================