Modifications to handle the situation where readline.h exists, but

history.h doesn't...previously, it was assumed that both existed, or
didn't exist...but this assumption fails on the one sparc_solaris box
that I have access to, and could exist in other circumstances

src/bin/psql/psql.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *    $Header: /cvsroot/pgsql/src/bin/psql/Attic/psql.c,v 1.50 1997/01/25 03:51:59 scrappy Exp $
+ *    $Header: /cvsroot/pgsql/src/bin/psql/Attic/psql.c,v 1.51 1997/01/25 21:58:08 scrappy Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -35,11 +35,15 @@
 #else
 # ifdef HAVE_READLINE_H
 #  include <readline.h>
+#  ifdef HAVE_HISTORY_H
 #   include <history.h>
+#  endif
 # else
 #  include <readline/readline.h>
+#  ifdef HAVE_READLINE_HISTORY_H
 #   include <readline/history.h>
 #  endif
+# endif
 #endif
 
 #define PROMPT "=> "