Make url-gateway-broken-resolution obsolete

* lisp/url/url-gw.el (url-gateway-broken-resolution)
(url-gateway-nslookup-program, url-gateway-nslookup-host): Make obsolete.
* doc/misc/url.texi (Broken hostname resolution): Delete commented
out section.

3 files changed, 21 insertions, 39 deletions

diff --git a/doc/misc/url.texi b/doc/misc/url.texi
index b5a6cb0e6a1..e6636e32507 100644
--- a/doc/misc/url.texi
+++ b/doc/misc/url.texi
@@ -1149,40 +1149,6 @@ If this variable is non-@code{nil} new network connections are never
 opened by the URL library.
 @end defvar
 
-@c @node Broken hostname resolution
-@c @subsection Broken Hostname Resolution
-
-@c @cindex hostname resolver
-@c @cindex resolver, hostname
-@c Some C libraries do not include the hostname resolver routines in
-@c their static libraries.  If Emacs was linked statically, and was not
-@c linked with the resolver libraries, it will not be able to get to any
-@c machines off the local network.  This is characterized by being able
-@c to reach someplace with a raw ip number, but not its hostname
-@c (@url{https://129.79.254.191/} works, but
-@c @url{https://www.cs.indiana.edu/} doesn't).  This used to happen on
-@c SunOS4 and Ultrix, but is now probably now rare.  If Emacs can't be
-@c rebuilt linked against the resolver library, it can use the external
-@c @command{nslookup} program instead.
-
-@c @defopt url-gateway-broken-resolution
-@c @cindex @code{nslookup} program
-@c @cindex program, @code{nslookup}
-@c If non-@code{nil}, this variable says to use the program specified by
-@c @code{url-gateway-nslookup-program} program to do hostname resolution.
-@c @end defopt
-
-@c @defopt url-gateway-nslookup-program
-@c The name of the program to do hostname lookup if Emacs can't do it
-@c directly.  This program should expect a single argument on the command
-@c line---the hostname to resolve---and should produce output similar to
-@c the standard Unix @command{nslookup} program:
-@c @example
-@c Name: www.cs.indiana.edu
-@c Address: 129.79.254.191
-@c @end example
-@c @end defopt
-
 @node History
 @section History
 
diff --git a/etc/NEWS b/etc/NEWS
index d7c6edefe4b..f965cf10561 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -719,6 +719,15 @@ Checkdoc now warns if the first line of an Emacs Lisp file does not
 end with a "-*- lexical-binding: t -*-" cookie.  Customize the user
 option 'checkdoc-lexical-binding-flag' to nil to disable this warning.
 
+** url
+
++++
+*** 'url-gateway-broken-resolution' is now obsolete.
+This option was intended for use on SunOS 4.x and Ultrix systems,
+neither of which have been supported by Emacs since version 23.1.
+The user option 'url-gateway-nslookup-program' and the function
+'url-gateway-nslookup-host' are consequently also obsolete.
+
 
 * New Modes and Packages in Emacs 30.1
 
diff --git a/lisp/url/url-gw.el b/lisp/url/url-gw.el
index 4d7297f6f2e..568ce8679f5 100644
--- a/lisp/url/url-gw.el
+++ b/lisp/url/url-gw.el
@@ -1,6 +1,6 @@
 ;;; url-gw.el --- Gateway munging for URL loading  -*- lexical-binding: t; -*-
 
-;; Copyright (C) 1997-1998, 2004-2023 Free Software Foundation, Inc.
+;; Copyright (C) 1997-2023 Free Software Foundation, Inc.
 
 ;; Author: Bill Perry <wmperry@gnu.org>
 ;; Maintainer: emacs-devel@gnu.org
@@ -97,21 +97,27 @@ This list will be executed as a command after logging in via telnet."
 
 (defcustom url-gateway-broken-resolution nil
   "Whether to use nslookup to resolve hostnames.
-This should be used when your version of Emacs cannot correctly use DNS,
-but your machine can.  This usually happens if you are running a statically
-linked Emacs under SunOS 4.x."
+This should be used when your version of Emacs cannot correctly
+use DNS, but your machine can.
+
+This used to happen on SunOS 4.x and Ultrix when Emacs was linked
+statically, and also was not linked with the resolver libraries.
+Those systems are no longer supported by Emacs."
   :type 'boolean
   :group 'url-gateway)
+(make-obsolete-variable 'url-gateway-broken-resolution nil "30.1")
 
 (defcustom url-gateway-nslookup-program "nslookup"
   "If non-nil then a string naming nslookup program."
   :type '(choice (const :tag "None" :value nil) string)
   :group 'url-gateway)
+(make-obsolete-variable 'url-gateway-nslookup-program nil "30.1")
 
 ;; Stolen from ange-ftp
 ;;;###autoload
 (defun url-gateway-nslookup-host (host)
   "Attempt to resolve the given HOST using nslookup if possible."
+  (declare (obsolete nil "30.1"))
   (interactive "sHost:  ")
   (if url-gateway-nslookup-program
       (let ((proc (start-process " *nslookup*" " *nslookup*"
@@ -237,7 +243,8 @@ overriding the value of `url-gateway-method'."
 
       ;; If the user told us to do DNS for them, do it.
       (if url-gateway-broken-resolution
-          (setq host (url-gateway-nslookup-host host)))
+          (with-suppressed-warnings ((obsolete url-gateway-nslookup-host))
+            (setq host (url-gateway-nslookup-host host))))
 
       ;; This is a clean way to ensure the new process inherits the
       ;; right coding systems in both Emacs and XEmacs.