commit bash-20130920 snapshot

lib/readline/doc/rltech.texi

@@ -1539,12 +1539,21 @@ The default value of @code{rl_catch_signals} is 1.
 @end deftypevar
 
 @deftypevar int rl_catch_sigwinch
-If this variable is non-zero, Readline will install a signal handler for
-@code{SIGWINCH}.
+If this variable is set to a non-zero value,
+Readline will install a signal handler for @code{SIGWINCH}.
 
 The default value of @code{rl_catch_sigwinch} is 1.
 @end deftypevar
 
+@deftypevar int rl_change_environment
+If this variable is set to a non-zero value,
+and Readline is handling @code{SIGWINCH}, Readline will modify the
+@var{LINES} and @var{COLUMNS} environment variables upon receipt of a
+@code{SIGWINCH}
+
+The default value of @code{rl_change_environment} is 1.
+@end deftypevar
+
 If an application does not wish to have Readline catch any signals, or
 to handle signals other than those Readline catches (@code{SIGHUP},
 for example), 

lib/readline/readline.h

@@ -617,6 +617,10 @@ extern int rl_catch_signals;
    to do that. */
 extern int rl_catch_sigwinch;
 
+/* If non-zero, the readline SIGWINCH handler will modify LINES and
+   COLUMNS in the environment. */
+extern int rl_change_environment;
+
 /* Completion variables. */
 /* Pointer to the generator function for completion_matches ().
    NULL means to use rl_filename_completion_function (), the default

lib/readline/terminal.c

@@ -81,11 +81,15 @@ static void _win_get_screensize PARAMS((int *, int *));
 static void _emx_get_screensize PARAMS((int *, int *));
 #endif
 
-/*  If the calling application sets this to a non-zero value, readline will
-    use the $LINES and $COLUMNS environment variables to set its idea of the
-    window size before interrogating the kernel. */
+/* If the calling application sets this to a non-zero value, readline will
+   use the $LINES and $COLUMNS environment variables to set its idea of the
+   window size before interrogating the kernel. */
 int rl_prefer_env_winsize = 0;
 
+/* If this is non-zero, readline will set LINES and COLUMNS in the
+   environment when it handles SIGWINCH. */
+int rl_change_environment = 1;
+
 /* **************************************************************** */
 /*								    */
 /*			Terminal and Termcap			    */
@@ -305,7 +309,8 @@ _rl_get_screen_size (tty, ignore_env)
   /* If we're being compiled as part of bash, set the environment
      variables $LINES and $COLUMNS to new values.  Otherwise, just
      do a pair of putenv () or setenv () calls. */
-  sh_set_lines_and_columns (_rl_screenheight, _rl_screenwidth);
+  if (rl_change_environment)
+    sh_set_lines_and_columns (_rl_screenheight, _rl_screenwidth);
 
   if (_rl_term_autowrap == 0)
     _rl_screenwidth--;