lisp/net-utils.el

   1 ;;; net-utils.el --- Network functions
   2
   3 ;; Author:  Peter Breton <pbreton@cs.umb.edu>
   4 ;; Created: Sun Mar 16 1997
   5 ;; Keywords: network communications
   6 ;; Time-stamp: <1998-06-13 06:19:01 pbreton>
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software; you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation; either version 2, or (at your option)
  13 ;; any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  22 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  23 ;; Boston, MA 02111-1307, USA.
  24
  25 ;;; Commentary:
  26 ;;
  27 ;; There are three main areas of functionality:
  28 ;;
  29 ;; * Wrap common network utility programs (ping, traceroute, netstat,
  30 ;; nslookup, arp, route). Note that these wrappers are of the diagnostic
  31 ;; functions of these programs only.
  32 ;;
  33 ;; * Implement some very basic protocols in Emacs Lisp (finger and whois)
  34 ;;
  35 ;; * Support connections to HOST/PORT, generally for debugging and the like.
  36 ;; In other words, for doing much the same thing as "telnet HOST PORT", and
  37 ;; then typing commands.
  38 ;;
  39 ;; PATHS
  40 ;;
  41 ;; On some systems, some of these programs are not in normal user path,
  42 ;; but rather in /sbin, /usr/sbin, and so on.
  43
  44
  45 ;;; Code:
  46 (eval-when-compile
  47   (require 'comint))
  48
  49 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  50 ;; Customization Variables
  51 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  52
  53 (defgroup net-utils nil
  54   "Network utility functions."
  55   :prefix "net-utils-"
  56   :group 'comm
  57   :version "20.3"
  58   )
  59
  60 (defcustom net-utils-remove-ctl-m
  61   (member system-type (list 'windows-nt 'msdos))
  62   "If non-nil, remove control-Ms from output."
  63   :group 'net-utils
  64   :type  'boolean
  65   )
  66
  67 (defcustom traceroute-program
  68   (if (eq system-type 'windows-nt)
  69       "tracert"
  70     "traceroute")
  71   "Program to trace network hops to a destination."
  72   :group 'net-utils
  73   :type  'string
  74   )
  75
  76 (defcustom traceroute-program-options nil
  77   "Options for the traceroute program."
  78   :group 'net-utils
  79   :type  '(repeat string)
  80   )
  81
  82 (defcustom ping-program "ping"
  83   "Program to send network test packets to a host."
  84   :group 'net-utils
  85   :type  'string
  86   )
  87
  88 ;; On Linux and Irix, the system's ping program seems to send packets
  89 ;; indefinitely unless told otherwise
  90 (defcustom ping-program-options
  91   (and (memq system-type (list 'linux 'gnu/linux 'irix))
  92        (list "-c" "4"))
  93   "Options for the ping program.
  94 These options can be used to limit how many ICMP packets are emitted."
  95   :group 'net-utils
  96   :type  '(repeat string)
  97   )
  98
  99 (defcustom ipconfig-program
 100   (if (eq system-type 'windows-nt)
 101       "ipconfig"
 102     "ifconfig")
 103   "Program to print network configuration information."
 104   :group 'net-utils
 105   :type  'string
 106   )
 107
 108 (defcustom ipconfig-program-options
 109    (list
 110     (if (eq system-type 'windows-nt)
 111         "/all" "-a"))
 112   "Options for ipconfig-program."
 113   :group 'net-utils
 114   :type  '(repeat string)
 115   )
 116
 117 (defcustom netstat-program  "netstat"
 118   "Program to print network statistics."
 119   :group 'net-utils
 120   :type  'string
 121   )
 122
 123 (defcustom netstat-program-options
 124   (list "-a")
 125   "Options for netstat-program."
 126   :group 'net-utils
 127   :type  '(repeat string)
 128   )
 129
 130 (defcustom arp-program  "arp"
 131   "Program to print IP to address translation tables."
 132   :group 'net-utils
 133   :type  'string
 134   )
 135
 136 (defcustom arp-program-options
 137   (list "-a")
 138   "Options for arp-program."
 139   :group 'net-utils
 140   :type  '(repeat string)
 141   )
 142
 143 (defcustom route-program
 144   (if (eq system-type 'windows-nt)
 145       "route"
 146     "netstat")
 147   "Program to print routing tables."
 148   :group 'net-utils
 149   :type  'string
 150   )
 151
 152 (defcustom route-program-options
 153   (if (eq system-type 'windows-nt)
 154       (list "print")
 155     (list "-r"))
 156   "Options for route-program."
 157   :group 'net-utils
 158   :type  '(repeat string)
 159   )
 160
 161 (defcustom nslookup-program  "nslookup"
 162   "Program to interactively query DNS information."
 163   :group 'net-utils
 164   :type  'string
 165   )
 166
 167 (defcustom nslookup-program-options  nil
 168   "List of options to pass to the nslookup program."
 169   :group 'net-utils
 170   :type  '(repeat string)
 171   )
 172
 173 (defcustom nslookup-prompt-regexp "^> "
 174   "Regexp to match the nslookup prompt."
 175   :group 'net-utils
 176   :type  'regexp
 177   )
 178
 179 (defcustom ftp-program "ftp"
 180   "Progam to run to do FTP transfers."
 181   :group 'net-utils
 182   :type  'string
 183   )
 184
 185 (defcustom ftp-program-options nil
 186   "List of options to pass to the FTP program."
 187   :group 'net-utils
 188   :type  '(repeat string)
 189   )
 190
 191 (defcustom ftp-prompt-regexp "^ftp>"
 192   "Regexp which matches the FTP program's prompt."
 193   :group 'net-utils
 194   :type  'regexp
 195   )
 196
 197 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 198 ;; Nslookup goodies
 199 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 200
 201 (defconst nslookup-font-lock-keywords
 202   (and window-system
 203        (progn
 204          (require 'font-lock)
 205          (list
 206           (list nslookup-prompt-regexp 0 font-lock-reference-face)
 207           (list "^[A-Za-z0-9 _]+:"     0 font-lock-type-face)
 208           (list "\\<\\(SOA\\|NS\\|MX\\|A\\|CNAME\\)\\>"
 209                 1 font-lock-keyword-face)
 210           ;; Dotted quads
 211           (list
 212            (mapconcat 'identity
 213                       (make-list 4 "[0-9]+")
 214                       "\\.")
 215            0 font-lock-variable-name-face)
 216           ;; Host names
 217           (list
 218            (let ((host-expression "[-A-Za-z0-9]+"))
 219              (concat
 220               (mapconcat 'identity
 221                          (make-list 2 host-expression)
 222                          "\\.")
 223               "\\(\\." host-expression "\\)*")
 224              )
 225            0 font-lock-variable-name-face)
 226           )))
 227          "Expressions to font-lock for nslookup.")
 228
 229 (defvar nslookup-abbrev-table (make-abbrev-table)
 230   "Abbrev table for nslookup.")
 231
 232 (define-abbrev nslookup-abbrev-table "e"   "exit")
 233 (define-abbrev nslookup-abbrev-table "f"   "finger")
 234 (define-abbrev nslookup-abbrev-table "h"   "help")
 235 (define-abbrev nslookup-abbrev-table "lse" "lserver")
 236 (define-abbrev nslookup-abbrev-table "r"   "root")
 237 (define-abbrev nslookup-abbrev-table "s"   "set")
 238 (define-abbrev nslookup-abbrev-table "se"  "server")
 239 (define-abbrev nslookup-abbrev-table "v"   "viewer")
 240
 241 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 242 ;; FTP goodies
 243 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 244
 245 (defvar ftp-abbrev-table (make-abbrev-table)
 246   "Abbrev table for ftp.")
 247
 248 (define-abbrev ftp-abbrev-table "q"    "quit")
 249 (define-abbrev ftp-abbrev-table "g"    "get")
 250 (define-abbrev ftp-abbrev-table "p"    "prompt")
 251 (define-abbrev ftp-abbrev-table "anon" "anonymous")
 252
 253 (defconst ftp-font-lock-keywords
 254   (and window-system
 255        (progn
 256          (require 'font-lock)
 257          (list
 258           (list ftp-prompt-regexp 0 font-lock-reference-face)))))
 259
 260
 261 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 262 ;; Utility functions
 263 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 264
 265 ;; Simplified versions of some at-point functions from ffap.el.
 266 ;; It's not worth loading all of ffap just for these.
 267 (defun net-utils-machine-at-point ()
 268   (let ((pt (point)))
 269     (buffer-substring-no-properties
 270      (save-excursion
 271        (skip-chars-backward "-a-zA-Z0-9.")
 272        (point))
 273      (save-excursion
 274        (skip-chars-forward "-a-zA-Z0-9.")
 275        (skip-chars-backward "." pt)
 276        (point)))))
 277
 278 (defun net-utils-url-at-point ()
 279   (let ((pt (point)))
 280     (buffer-substring-no-properties
 281      (save-excursion
 282        (skip-chars-backward "--:=&?$+@-Z_a-z~#,%")
 283        (skip-chars-forward "^A-Za-z0-9" pt)
 284        (point))
 285      (save-excursion
 286        (skip-chars-forward "--:=&?$+@-Z_a-z~#,%")
 287        (skip-chars-backward ":;.,!?" pt)
 288        (point)))))
 289
 290
 291 (defun net-utils-remove-ctrl-m-filter (process output-string)
 292   "Remove trailing control Ms."
 293   (let ((old-buffer (current-buffer))
 294         (filtered-string output-string))
 295     (unwind-protect
 296         (let ((moving))
 297           (set-buffer (process-buffer process))
 298           (setq moving (= (point) (process-mark process)))
 299
 300           (while (string-match "\r" filtered-string)
 301                (setq filtered-string
 302                      (replace-match "" nil nil filtered-string)))
 303
 304           (save-excursion
 305             ;; Insert the text, moving the process-marker.
 306             (goto-char (process-mark process))
 307             (insert filtered-string)
 308             (set-marker (process-mark process) (point)))
 309           (if moving (goto-char (process-mark process))))
 310       (set-buffer old-buffer))))
 311
 312 (defmacro net-utils-run-program (name header program &rest args)
 313   "Run a network information program."
 314   (`
 315    (let ((buf (get-buffer-create (concat "*" (, name) "*"))))
 316      (set-buffer buf)
 317      (erase-buffer)
 318      (insert (, header) "\n")
 319      (set-process-filter
 320       (apply 'start-process (, name) buf (, program) (,@ args))
 321       'net-utils-remove-ctrl-m-filter)
 322      (display-buffer buf))))
 323
 324 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 325 ;; Wrappers for external network programs
 326 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 327
 328 ;;;###autoload
 329 (defun traceroute (target)
 330   "Run traceroute program for TARGET."
 331   (interactive "sTarget: ")
 332   (let ((options
 333          (if traceroute-program-options
 334              (append traceroute-program-options (list target))
 335            (list target))))
 336     (net-utils-run-program
 337      (concat "Traceroute" " " target)
 338      (concat "** Traceroute ** " traceroute-program " ** " target)
 339      traceroute-program
 340      options
 341      )))
 342
 343 ;;;###autoload
 344 (defun ping (host)
 345   "Ping HOST.
 346 If your system's ping continues until interrupted, you can try setting
 347 `ping-program-options'."
 348   (interactive
 349    (list (read-from-minibuffer "Ping host: " (net-utils-machine-at-point))))
 350   (let ((options
 351          (if ping-program-options
 352              (append ping-program-options (list host))
 353            (list host))))
 354     (net-utils-run-program
 355      (concat "Ping" " " host)
 356      (concat "** Ping ** " ping-program " ** " host)
 357      ping-program
 358      options
 359      )))
 360
 361 ;;;###autoload
 362 (defun ipconfig ()
 363   "Run ipconfig program."
 364   (interactive)
 365   (net-utils-run-program
 366    "Ipconfig"
 367    (concat "** Ipconfig ** " ipconfig-program " ** ")
 368    ipconfig-program
 369    ipconfig-program-options
 370    ))
 371
 372 ;; This is the normal name on most Unixes.
 373 ;;;###autoload
 374 (defalias 'ifconfig 'ipconfig)
 375
 376 ;;;###autoload
 377 (defun netstat ()
 378   "Run netstat program."
 379   (interactive)
 380   (net-utils-run-program
 381    "Netstat"
 382    (concat "** Netstat ** " netstat-program " ** ")
 383    netstat-program
 384    netstat-program-options
 385    ))
 386
 387 ;;;###autoload
 388 (defun arp ()
 389   "Run the arp program."
 390   (interactive)
 391   (net-utils-run-program
 392    "Arp"
 393    (concat "** Arp ** " arp-program " ** ")
 394    arp-program
 395    arp-program-options
 396    ))
 397
 398 ;;;###autoload
 399 (defun route ()
 400   "Run the route program."
 401   (interactive)
 402   (net-utils-run-program
 403    "Route"
 404    (concat "** Route ** " route-program " ** ")
 405    route-program
 406    route-program-options
 407    ))
 408
 409 ;; FIXME -- Needs to be a process filter
 410 ;; (defun netstat-with-filter (filter)
 411 ;;   "Run netstat program."
 412 ;;   (interactive "sFilter: ")
 413 ;;   (netstat)
 414 ;;   (set-buffer (get-buffer "*Netstat*"))
 415 ;;   (goto-char (point-min))
 416 ;;   (delete-matching-lines filter)
 417 ;;   )
 418
 419 ;;;###autoload
 420 (defun nslookup-host (host)
 421   "Lookup the DNS information for HOST."
 422   (interactive
 423    (list (read-from-minibuffer "Lookup host: " (net-utils-machine-at-point))))
 424   (let ((options
 425          (if nslookup-program-options
 426              (append nslookup-program-options (list host))
 427            (list host))))
 428     (net-utils-run-program
 429      "Nslookup"
 430      (concat "** "
 431       (mapconcat 'identity
 432                 (list "Nslookup" host nslookup-program)
 433                 " ** "))
 434      nslookup-program
 435      options
 436      )))
 437
 438
 439 ;;;###autoload
 440 (defun nslookup ()
 441   "Run nslookup program."
 442   (interactive)
 443   (require 'comint)
 444   (comint-run nslookup-program)
 445   (set-process-filter (get-buffer-process "*nslookup*")
 446    'net-utils-remove-ctrl-m-filter)
 447   (set
 448    (make-local-variable 'font-lock-defaults)
 449    '((nslookup-font-lock-keywords)))
 450   (set
 451    (make-local-variable 'local-abbrev-table)
 452    nslookup-abbrev-table)
 453   (abbrev-mode t)
 454   (make-local-variable 'comint-prompt-regexp)
 455   (setq comint-prompt-regexp nslookup-prompt-regexp)
 456   )
 457
 458 ;; This is a lot less than ange-ftp, but much simpler.
 459 ;;;###autoload
 460 (defun ftp (host)
 461   "Run ftp program."
 462   (interactive "sFtp to Host: ")
 463   (require 'comint)
 464   (let ((buf (get-buffer-create (concat "*ftp [" host "]*"))))
 465     (set-buffer buf)
 466     (comint-mode)
 467     (comint-exec buf (concat "ftp-" host) ftp-program nil
 468                  (if ftp-program-options
 469                      (append (list host) ftp-program-options)
 470                    (list host)))
 471     (set
 472      (make-local-variable 'font-lock-defaults)
 473      '((ftp-font-lock-keywords)))
 474
 475     (make-local-variable 'comint-prompt-regexp)
 476     (setq comint-prompt-regexp ftp-prompt-regexp)
 477
 478     ;; Already buffer local!
 479     (setq comint-output-filter-functions
 480           (list 'comint-watch-for-password-prompt))
 481     (set
 482      (make-local-variable 'local-abbrev-table)
 483      ftp-abbrev-table)
 484     (abbrev-mode t)
 485     (switch-to-buffer-other-window buf)
 486     ))
 487
 488 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 489 ;; Network Connections
 490 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 491
 492 ;; Full list is available at:
 493 ;; ftp://ftp.isi.edu/in-notes/iana/assignments/port-numbers
 494 (defvar network-connection-service-alist
 495   (list
 496     (cons 'echo          7)
 497     (cons 'active-users 11)
 498     (cons 'daytime      13)
 499     (cons 'chargen      19)
 500     (cons 'ftp          21)
 501     (cons 'telnet       23)
 502     (cons 'smtp         25)
 503     (cons 'time         37)
 504     (cons 'whois        43)
 505     (cons 'gopher       70)
 506     (cons 'finger       79)
 507     (cons 'www          80)
 508     (cons 'pop2         109)
 509     (cons 'pop3         110)
 510     (cons 'sun-rpc      111)
 511     (cons 'nntp         119)
 512     (cons 'ntp          123)
 513     (cons 'netbios-name 137)
 514     (cons 'netbios-data 139)
 515     (cons 'irc          194)
 516     (cons 'https        443)
 517     (cons 'rlogin       513)
 518     )
 519   "Alist of services and associated TCP port numbers.
 520 This list in not complete.")
 521
 522 ;; Workhorse macro
 523 (defmacro run-network-program (process-name host port
 524                                             &optional initial-string)
 525   (`
 526    (let ((tcp-connection)
 527          (buf)
 528          )
 529     (setq buf (get-buffer-create (concat "*" (, process-name) "*")))
 530     (set-buffer buf)
 531     (or
 532      (setq tcp-connection
 533            (open-network-stream
 534             (, process-name)
 535             buf
 536             (, host)
 537             (, port)
 538             ))
 539      (error "Could not open connection to %s" (, host)))
 540     (erase-buffer)
 541     (set-marker (process-mark tcp-connection) (point-min))
 542     (set-process-filter tcp-connection 'net-utils-remove-ctrl-m-filter)
 543     (and (, initial-string)
 544          (process-send-string tcp-connection
 545                               (concat (, initial-string) "\r\n")))
 546     (display-buffer buf))))
 547
 548 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 549 ;; Simple protocols
 550 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 551
 552 ;; Finger protocol
 553 ;;;###autoload
 554 (defun finger (user host)
 555   "Finger USER on HOST."
 556   ;; One of those great interactive statements that's actually
 557   ;; longer than the function call! The idea is that if the user
 558   ;; uses a string like "pbreton@cs.umb.edu", we won't ask for the
 559   ;; host name. If we don't see an "@", we'll prompt for the host.
 560   (interactive
 561     (let* ((answer (read-from-minibuffer "Finger User: "
 562                                          (net-utils-url-at-point)))
 563            (index  (string-match (regexp-quote "@") answer)))
 564       (if index
 565           (list
 566            (substring answer 0 index)
 567            (substring answer (1+ index)))
 568         (list
 569          answer
 570          (read-from-minibuffer "At Host: " (net-utils-machine-at-point))))))
 571   (let* (
 572          (user-and-host (concat user "@" host))
 573          (process-name
 574           (concat "Finger [" user-and-host "]"))
 575          )
 576     (run-network-program
 577      process-name
 578      host
 579      (cdr (assoc 'finger network-connection-service-alist))
 580      user-and-host
 581      )))
 582
 583 (defcustom whois-server-name "whois.arin.net"
 584   "Default host name for the whois service."
 585   :group 'net-utils
 586   :type  'string
 587   )
 588
 589 (defcustom whois-server-list
 590   '(("whois.arin.net")     ; Networks, ASN's, and related POC's (numbers)
 591     ("rs.internic.net")  ; domain related info
 592     ("whois.abuse.net")
 593     ("whois.apnic.net")
 594     ("nic.ddn.mil")
 595     ("whois.nic.mil")
 596     ("whois.nic.gov")
 597     ("whois.ripe.net"))
 598   "A list of whois servers that can be queried."
 599   :group 'net-utils
 600   :type '(repeat (list string)))
 601
 602 (defcustom whois-server-tld
 603   '(("rs.internic.net" . "com")
 604     ("rs.internic.net" . "org")
 605     ("whois.ripe.net" . "be")
 606     ("whois.ripe.net" . "de")
 607     ("whois.ripe.net" . "dk")
 608     ("whois.ripe.net" . "it")
 609     ("whois.ripe.net" . "fi")
 610     ("whois.ripe.net" . "fr")
 611     ("whois.ripe.net" . "uk")
 612     ("whois.apnic.net" . "au")
 613     ("whois.apnic.net" . "ch")
 614     ("whois.apnic.net" . "hk")
 615     ("whois.apnic.net" . "jp")
 616     ("whois.nic.gov" . "gov")
 617     ("whois.nic.mil" . "mil"))
 618   "Alist to map top level domains to whois servers."
 619   :group 'net-utils
 620   :type '(repeat (cons string string)))
 621
 622 (defcustom whois-guess-server t
 623   "If non-nil then whois will try to deduce the appropriate whois
 624 server from the query.  If the query doesn't look like a domain or hostname
 625 then the server named by whois-server-name is used."
 626   :group 'net-utils
 627   :type 'boolean)
 628
 629
 630 (defun whois-get-tld (host)
 631   (do ((i (1- (length host)) (1- i))
 632        (max-len (- (length host) 4)))
 633       ((or (= i max-len) (char-equal (aref host i) ?.))
 634        (if (= i max-len) nil
 635          (substring host (1+ i))))))
 636
 637 ;; Whois protocol
 638 ;;;###autoload
 639 (defun whois (arg search-string)
 640   "Send SEARCH-STRING to server defined by the `whois-server-name' variable.
 641 If `whois-guess-server' is non-nil, then try to deduce the correct server
 642 from SEARCH-STRING.  With argument, prompt for whois server."
 643   (interactive "P\nsWhois: ")
 644   (let* ((whois-apropos-host (if whois-guess-server
 645                                  (rassoc (whois-get-tld search-string)
 646                                          whois-server-tld)
 647                                nil))
 648          (server-name (if whois-apropos-host
 649                           (car whois-apropos-host)
 650                         whois-server-name))
 651          (host
 652           (if arg
 653               (completing-read "Whois server name: "
 654                                whois-server-list nil nil "whois.")
 655             server-name)))
 656     (run-network-program
 657      "Whois"
 658      host
 659      (cdr (assoc 'whois network-connection-service-alist))
 660      search-string
 661      )))
 662
 663 (defcustom whois-reverse-lookup-server "whois.arin.net"
 664   "Server which provides inverse DNS mapping."
 665   :group 'net-utils
 666   :type  'string
 667   )
 668
 669 ;;;###autoload
 670 (defun whois-reverse-lookup ()
 671   (interactive)
 672   (let ((whois-server-name whois-reverse-lookup-server))
 673     (call-interactively 'whois)))
 674
 675 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 676 ;;; General Network connection
 677 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 678
 679 ;;;###autoload
 680 (defun network-connection-to-service (host service)
 681   "Open a network connection to SERVICE on HOST."
 682   (interactive
 683    (list
 684     (read-from-minibuffer "Host: " (net-utils-machine-at-point))
 685     (completing-read "Service: "
 686                      (mapcar
 687                       (function
 688                        (lambda (elt)
 689                          (list (symbol-name (car elt)))))
 690                       network-connection-service-alist))))
 691   (network-connection
 692    host
 693    (cdr (assoc (intern service) network-connection-service-alist)))
 694   )
 695
 696 ;;;###autoload
 697 (defun network-connection (host port)
 698   "Open a network connection to HOST on PORT."
 699   (interactive "sHost: \nnPort: ")
 700   (network-service-connection host (number-to-string port)))
 701
 702 (defun network-service-connection (host service)
 703   "Open a network connection to SERVICE on HOST."
 704   (require 'comint)
 705   (let (
 706         (process-name (concat "Network Connection [" host " " service "]"))
 707         (portnum (string-to-number service))
 708         )
 709     (or (zerop portnum) (setq service portnum))
 710     (make-comint
 711      process-name
 712      (cons host service))
 713     (pop-to-buffer (get-buffer (concat "*" process-name "*")))
 714     ))
 715
 716 (provide 'net-utils)
 717
 718 ;;; net-utils.el ends here