code.delx.au - gnu-emacs-elpa/blob - packages/multishell/multishell.el

   1 ;;; multishell.el --- facilitate multiple local and remote shell buffers
   2
   3 ;; Copyright (C) 1999-2016 Free Software Foundation, Inc. and Ken Manheimer
   4
   5 ;; Author: Ken Manheimer <ken.manheimer@gmail.com>
   6 ;; Version: 1.0.5
   7 ;; Created: 1999 -- first public availability
   8 ;; Keywords: processes
   9 ;; URL: https://github.com/kenmanheimer/EmacsMultishell
  10 ;;
  11 ;;; Commentary:
  12 ;;
  13 ;; Easily use and navigate multiple shell buffers, including remote shells.
  14 ;; Fundamentally, multishell is the function `multishell-pop-to-shell' -
  15 ;; a la `pop-to-buffer' - plus a keybinding. Together, they enable you to:
  16 ;;
  17 ;; * Get to the input point from wherever you are in a shell buffer,
  18 ;;   ... or to any of your shell buffers, from elsewhere inside emacs.
  19 ;;
  20 ;; * Use universal arguments to launch and choose among alternate shell buffers,
  21 ;; * ... and change which is the current default.
  22 ;;
  23 ;; * Easily restart disconnected shells, or shells from prior sessions
  24 ;; * ... the latter from Emacs builtin savehist minibuf history persistence
  25 ;;
  26 ;; * Append a path to a new shell name to launch a shell in that directory,
  27 ;; * ... and use a path with Emacs tramp syntax to launch a remote shell -
  28 ;;   for example:
  29 ;;
  30 ;;   * `/ssh:example.net:/` for a shell buffer in / on example.net.
  31 ;;     The buffer will be named "*example.net*".
  32 ;;
  33 ;;   * `#ex/ssh:example.net|sudo:root@example.net:/etc` for a root shell
  34 ;;     starting in /etc on example.net named "*#ex*".
  35 ;;
  36 ;;   * '\#intrn/ssh:corp.com|ssh:intern.corp.com|sudo:root@intern.corp.com:/etc'
  37 ;;     to go via corp.com to intern.corp.com, sudood to root, in /etc. Whee! (-:
  38 ;;     The buffer will be named "*#intrn*".
  39 ;;
  40 ;; * File visits will all be under the auspices of the account, and relative to
  41 ;;   the current directory, on the remote host.
  42 ;;
  43 ;; See the `multishell-pop-to-shell` docstring for details.
  44 ;;
  45 ;; Customize-group `multishell' to select and activate a keybinding and set
  46 ;; various behaviors. Customize-group `savehist' to preserve buffer
  47 ;; names/paths across emacs sessions.
  48 ;;
  49 ;; Please use
  50 ;; [the multishell repository](https://github.com/kenmanheimer/EmacsMultishell)
  51 ;; issue tracker to report problems, suggestions, etc.
  52 ;;
  53 ;; (NOTE - tramp sometimes has a problem opening a remote shell pointed at
  54 ;; a homedir, eg `/ssh:example.net:` or `/ssh:example.net:~`. When it
  55 ;; fails, it won't work for the rest of the session. Non-homedir remote
  56 ;; access isn't disrupted. Until this is fixed, you may need to start
  57 ;; remote shells with an explicit path, then cd ~.)
  58 ;;
  59 ;; Change Log:
  60 ;;
  61 ;; * 2016-01-16 1.0.5 Ken Manheimer:
  62 ;;   - History now includes paths, when designated
  63 ;;   - Actively track current directory in history entries that have a path.
  64 ;;     Custom control: multishell-history-entry-tracks-current-directory
  65 ;;   - Offer to remove shell's history entry when buffer is killed.
  66 ;;     (Currently the only UI mechanism to remove history entries.)
  67 ;;   - Fix - prevent duplicate entries for same name but different paths
  68 ;;   - Fix - recognize and respect tramp path syntax to start in home dir
  69 ;;     - But tramp bug, remote w/empty path (homedir) often fails, gets wedged.
  70 ;;   - Simplify history var name, migrate existing history if any from old name
  71 ;; * 2016-01-04 1.0.4 Ken Manheimer - Released to ELPA
  72 ;; * 2016-01-02 Ken Manheimer - working on this in public, but not yet released.
  73 ;;
  74 ;; TODO:
  75 ;;
  76 ;; * Isolate tramp sporadic failure to connect to remote+homedir (empty path)
  77 ;;   syntax
  78 ;;   (eg, /ssh:xyz.com|sudo:root@xyz.com: or /ssh:xyz.com|sudo:root@xyz.com:~)
  79 ;; * Find suitable, internally consistent ways to sort tidy completions, eg:
  80 ;;   - first list completions for active shells, then present but inactive,
  81 ;;     then historical
  82 ;;   - some way for user to toggle between presenting just buffer names vs
  83 ;;     full buffer/path
  84 ;;     - without cutting user off from easy editing of path
  85 ;; * Find proper method for setting field boundary at beginning of tramp path
  86 ;;   in the minibuffer, in order to see whether the field boundary magically
  87 ;;   enables tramp completion of the path.
  88 ;; * Assess whether option to delete history entry on kill-buffer is
  89 ;;   sufficient.
  90
  91 ;;; Code:
  92
  93 (require 'comint)
  94 (require 'shell)
  95
  96 (defgroup multishell nil
  97   "Allout extension that highlights outline structure graphically.
  98
  99 Customize `allout-widgets-auto-activation' to activate allout-widgets
 100 with allout-mode."
 101   :group 'shell)
 102
 103 (defcustom multishell-command-key "\M- "
 104   "The key to use if `multishell-activate-command-key' is true.
 105
 106 You can instead manually bind `multishell-pop-to-shell` using emacs
 107 lisp, eg: (global-set-key \"\\M- \" 'multishell-pop-to-shell)."
 108   :type 'key-sequence
 109   :group 'multishell)
 110
 111 (defvar multishell--responsible-for-command-key nil
 112   "Coordination for multishell key assignment.")
 113 (defun multishell-activate-command-key-setter (symbol setting)
 114   "Implement `multishell-activate-command-key' choice."
 115   (set-default 'multishell-activate-command-key setting)
 116   (when (or setting multishell--responsible-for-command-key)
 117     (multishell-implement-command-key-choice (not setting))))
 118 (defun multishell-implement-command-key-choice (&optional unbind)
 119   "If settings dicate, implement binding of multishell command key.
 120
 121 If optional UNBIND is true, globally unbind the key.
 122
 123 * `multishell-activate-command-key' - Set this to get the binding or not.
 124 * `multishell-command-key' - The key to use for the binding, if appropriate."
 125   (cond (unbind
 126          (when (and (boundp 'multishell-command-key) multishell-command-key)
 127            (global-unset-key multishell-command-key)))
 128         ((not (and (boundp 'multishell-activate-command-key)
 129                    (boundp 'multishell-command-key)))
 130          nil)
 131         ((and multishell-activate-command-key multishell-command-key)
 132          (setq multishell--responsible-for-command-key t)
 133          (global-set-key multishell-command-key 'multishell-pop-to-shell))))
 134
 135 (defcustom multishell-activate-command-key nil
 136   "Set this to impose the `multishell-command-key' binding.
 137
 138 You can instead manually bind `multishell-pop-to-shell` using emacs
 139 lisp, eg: (global-set-key \"\\M- \" 'multishell-pop-to-shell)."
 140   :type 'boolean
 141   :set 'multishell-activate-command-key-setter
 142   :group 'multishell)
 143
 144 ;; Assert the customizations whenever the package is loaded:
 145 (with-eval-after-load "multishell"
 146   (multishell-implement-command-key-choice))
 147
 148 (defcustom multishell-pop-to-frame nil
 149   "*If non-nil, jump to a frame already showing the shell, if another is.
 150
 151 Otherwise, disregard already-open windows on the shell if they're
 152 in another frame, and open a new window on the shell in the
 153 current frame.
 154
 155 \(Use `pop-up-windows' to change multishell other-buffer vs
 156 current-buffer behavior.)"
 157   :type 'boolean
 158   :group 'multishell)
 159
 160 (defcustom multishell-history-entry-tracks-current-directory t
 161   "Modify shell buffer's multishell entry to track the current directory.
 162
 163 When set, the path part of the name/path entry for each shell
 164 will track the current directory of the shell with emacs. If
 165 `savehist' is active, the directory tracking will extend across
 166 emacs sessions."
 167  :type 'boolean
 168  :group 'multishell)
 169
 170 (defvar multishell-history nil
 171   "Name/path entries, most recent first.")
 172 (when (and (not multishell-history)
 173            (boundp 'multishell-buffer-name-history)
 174            multishell-buffer-name-history)
 175   ;; Migrate few users who had old var to new.
 176   (setq multishell-history multishell-buffer-name-history)
 177  )
 178
 179 (defvar multishell-primary-name "*shell*"
 180   "Shell name to use for un-modified multishell-pop-to-shell buffer target.")
 181
 182 ;; Multiple entries happen because completion also adds name to history.
 183 (defun multishell-register-name-to-path (name path)
 184   "Add or replace entry associating NAME with PATH in `multishell-history'.
 185
 186 If NAME already had a PATH and new PATH is empty, retain the prior one.
 187
 188 Promote added/changed entry to the front of the list."
 189   ;; Add or promote to the front, tracking path changes in the process.
 190   (let* ((entries (multishell-history-entries name))
 191          (path (or path "")))
 192     (dolist (entry entries)
 193       (when (string= path "")
 194         ;; Retain explicit established path.
 195         (setq path (cadr (multishell-split-entry-name-and-tramp entry))))
 196       (setq multishell-history (delete entry multishell-history)))
 197     (setq multishell-history (push (concat name path)
 198                                    multishell-history))))
 199
 200 (defun multishell-history-entries (name)
 201   "Return `multishell-history' entry that starts with NAME, or nil if none."
 202   (let ((match-expr (concat "^" name "\\\(/.*$\\\)?"))
 203         got)
 204     (dolist (entry multishell-history)
 205       (when (and (string-match match-expr entry)
 206                  (not (member entry got)))
 207         (setq got (cons entry got))))
 208     got))
 209
 210 (defun multishell-pop-to-shell (&optional arg)
 211   "Easily navigate to and within multiple shell buffers, local and remote.
 212
 213 Use universal arguments to launch and choose between alternate
 214 shell buffers and to select which is default.  Append a path to
 215 a new shell name to launch a shell in that directory, and use
 216 Emacs tramp syntax to launch a remote shell.
 217
 218 Customize-group `multishell' to set up a key binding and tweak behaviors.
 219
 220 ==== Basic operation:
 221
 222  - If the current buffer is shell-mode (or shell-mode derived)
 223    buffer then focus is moved to the process input point.
 224
 225    \(You can use a universal argument go to a different shell
 226    buffer when already in a buffer that has a process - see
 227    below.)
 228
 229  - If not in a shell buffer (or with universal argument), go to a
 230    window that is already showing the (a) shell buffer, if any.
 231
 232    In this case, the cursor is left in its prior position in the
 233    shell buffer. Repeating the command will then go to the
 234    process input point, per the first item in this list.
 235
 236    We respect `pop-up-windows', so you can adjust it to set the
 237    other-buffer/same-buffer behavior.
 238
 239  - Otherwise, start a new shell buffer, using the current
 240    directory as the working directory.
 241
 242 If a buffer with the resulting name exists and its shell process
 243 was disconnected or otherwise stopped, it's resumed.
 244
 245 ===== Universal arg to start and select between named shell buffers:
 246
 247 You can name alternate shell buffers to create or return to using
 248 single or doubled universal arguments:
 249
 250  - With a single universal argument, prompt for the buffer name
 251    to use (without the asterisks that shell mode will put around
 252    the name), defaulting to 'shell'.
 253
 254    Completion is available.
 255
 256    This combination makes it easy to start and switch between
 257    multiple shell buffers.
 258
 259  - A double universal argument will prompt for the name *and* set
 260    the default to that name, so the target shell becomes the
 261    primary.
 262
 263 ===== Select starting directory and remote host:
 264
 265 The shell buffer name you give to the prompt for a universal arg
 266 can include an appended path. That will be used for the startup
 267 directory. You can use tramp remote syntax to specify a remote
 268 shell. If there is an element after a final '/', that's used for
 269 the buffer name. Otherwise, the host, domain, or path is used.
 270
 271 For example:
 272
 273 * Use '/ssh:example.net:/home/myaccount' for a shell buffer in
 274   /home/myaccount on example.net; the buffer will be named
 275   \"*example.net*\".
 276 * '\#ex/ssh:example.net|sudo:root@example.net:/etc' for a root
 277   shell in /etc on example.net named \"*#ex*\".
 278 * '\#in/ssh:corp.com|ssh:internal.corp.com|sudo:root@internal.corp.com:/etc'
 279   for a root shell name \"*in*\" in /etc on internal.corp.com, via host
 280   corp.com.
 281
 282 \(NOTE that there is a problem with specifying a remote homedir using
 283 tramp syntax, eg '/ssh:example.net:'. That sometimes fails on an obscure
 284 bug - particularly for remote with empty path (homedir) syntax. Until fixed,
 285 you may need to start remote shells with an explicit path, then cd ~.)
 286
 287 You can change the startup path for a shell buffer by editing it
 288 at the completion prompt. The new path will be preserved in
 289 history but will not take effect for an already-running shell.
 290
 291 To remove a shell buffer's history entry, kill the buffer and
 292 affirm removal of the entry when prompted.
 293
 294 ===== Activate savehist to retain shell buffer names and paths across Emacs sessions:
 295
 296 To have emacs maintain your history of shell buffer names and paths,
 297 customize the savehist group to activate savehist."
 298
 299   (interactive "P")
 300
 301   (let* ((from-buffer (current-buffer))
 302          (from-buffer-is-shell (derived-mode-p 'shell-mode))
 303          (doublearg (equal arg '(16)))
 304          (target-name-and-path
 305           (multishell-derive-target-name-and-path
 306            (if arg
 307                (multishell-read-bare-shell-buffer-name
 308                 (format "Shell buffer name [%s]%s "
 309                         (substring-no-properties
 310                          multishell-primary-name
 311                          1 (- (length multishell-primary-name) 1))
 312                         (if doublearg " <==" ":"))
 313                 multishell-primary-name)
 314              multishell-primary-name)))
 315          (use-default-dir (cadr target-name-and-path))
 316          (target-shell-buffer-name (car target-name-and-path))
 317          (curr-buff-proc (get-buffer-process from-buffer))
 318          (target-buffer (if from-buffer-is-shell
 319                             from-buffer
 320                           (let ((got (get-buffer target-shell-buffer-name)))
 321                             (if (buffer-live-p got)
 322                                 got
 323                               (kill-buffer got)
 324                               (get-buffer target-shell-buffer-name)))))
 325          inwin
 326          already-there)
 327
 328     (when doublearg
 329       (setq multishell-primary-name target-shell-buffer-name))
 330
 331     ;; Situate:
 332
 333     (cond
 334
 335      ((and (or curr-buff-proc from-buffer-is-shell)
 336            (not arg)
 337            (eq from-buffer target-buffer)
 338            (not (eq target-shell-buffer-name (buffer-name from-buffer))))
 339       ;; In a shell buffer, but not named - stay in buffer, but go to end.
 340       (setq already-there t))
 341
 342      ((string= (buffer-name) target-shell-buffer-name)
 343       ;; Already in the specified shell buffer:
 344       (setq already-there t))
 345
 346      ((or (not target-buffer)
 347           (not (setq inwin
 348                      (multishell-get-visible-window-for-buffer target-buffer))))
 349       ;; No preexisting shell buffer, or not in a visible window:
 350       (pop-to-buffer target-shell-buffer-name pop-up-windows))
 351
 352        ;; Buffer exists and already has a window - jump to it:
 353      (t (if (and multishell-pop-to-frame
 354                  inwin
 355                  (not (equal (window-frame (selected-window))
 356                              (window-frame inwin))))
 357             (select-frame-set-input-focus (window-frame inwin)))
 358         (if (not (string= (buffer-name (current-buffer))
 359                           target-shell-buffer-name))
 360             (pop-to-buffer target-shell-buffer-name t))))
 361
 362     ;; We're in the buffer. Activate:
 363
 364     (if (not (comint-check-proc (current-buffer)))
 365         (multishell-start-shell-in-buffer (buffer-name (current-buffer))
 366                                           use-default-dir))
 367
 368     ;; If the destination buffer has a stopped process, resume it:
 369     (let ((process (get-buffer-process (current-buffer))))
 370       (if (and process (equal 'stop (process-status process)))
 371           (continue-process process)))
 372     (multishell-register-name-to-path (multishell-unbracket-asterisks
 373                                        target-shell-buffer-name)
 374                                       use-default-dir)
 375     (when (or already-there
 376              (equal (current-buffer) from-buffer))
 377       (goto-char (point-max))
 378       (and (get-buffer-process from-buffer)
 379            (goto-char (process-mark (get-buffer-process from-buffer)))))))
 380
 381 (defun multishell-kill-buffer-query-function ()
 382   "Offer to remove multishell-history entry for buffer."
 383   ;; Removal choice is crucial, so users can, eg, kill and a runaway shell
 384   ;; and keep the history entry to easily restart it.
 385   ;;
 386   ;; We use kill-buffer-query-functions instead of kill-buffer-hook because:
 387   ;;
 388   ;; 1. It enables the user to remove the history without killing the buffer,
 389   ;;    by cancelling the kill-buffer process after affirming history removal.
 390   ;; 2. kill-buffer-hooks often fails to run when killing shell buffers!
 391   ;;    I've failed to resolve that, and like the first reason well enough.
 392
 393   ;; (Use condition-case to avoid inadvertant disruption of kill-buffer
 394   ;; activity.  kill-buffer happens behind the scenes a whole lot.)
 395   (condition-case anyerr
 396       (let ((entries (and (derived-mode-p 'shell-mode)
 397                           (multishell-history-entries
 398                            (multishell-unbracket-asterisks (buffer-name))))))
 399         (dolist (entry entries)
 400           (when (and entry
 401                      (y-or-n-p (format "Remove multishell history entry `%s'? "
 402                                        entry)))
 403             (setq multishell-history
 404                   (delete entry multishell-history)))))
 405     (error nil))
 406   t)
 407 (add-hook 'kill-buffer-query-functions 'multishell-kill-buffer-query-function)
 408
 409 (defun multishell-get-visible-window-for-buffer (buffer)
 410   "Return visible window containing buffer."
 411   (catch 'got-a-vis
 412     (walk-windows
 413      (function (lambda (win)
 414                  (if (and (eq (window-buffer win) buffer)
 415                           (equal (frame-parameter
 416                                   (selected-frame) 'display)
 417                                  (frame-parameter
 418                                   (window-frame win) 'display)))
 419                      (throw 'got-a-vis win))))
 420      nil 'visible)
 421     nil))
 422
 423 (defun multishell-read-bare-shell-buffer-name (prompt default)
 424   "PROMPT for shell buffer name, sans asterisks.
 425
 426 Return the supplied name bracketed with the asterisks, or specified DEFAULT
 427 on empty input."
 428   (let* ((candidates
 429           (append
 430            ;; Plain shell buffer names appended with names from name/path hist:
 431            (remq nil
 432                  (mapcar (lambda (buffer)
 433                            (let* ((name (multishell-unbracket-asterisks
 434                                          (buffer-name buffer))))
 435                              (and (buffer-live-p buffer)
 436                                   (with-current-buffer buffer
 437                                     ;; Shell mode buffers.
 438                                     (derived-mode-p 'shell-mode))
 439                                   (not (multishell-history-entries name))
 440                                   name)))
 441                          (buffer-list)))
 442            multishell-history))
 443          (got (completing-read prompt
 444                                ;; COLLECTION:
 445                                (reverse candidates)
 446                                ;; PREDICATE:
 447                                nil
 448                                ;; REQUIRE-MATCH:
 449                                'confirm
 450                                ;; INITIAL-INPUT
 451                                nil
 452                                ;; HIST:
 453                                'multishell-history)))
 454     (if (not (string= got ""))
 455         (multishell-bracket-asterisks got)
 456       default)))
 457
 458 (defun multishell-derive-target-name-and-path (path-ish)
 459   "Give tramp-style PATH-ISH, determine target name and default directory.
 460
 461 The name is the part of the string before the initial '/' slash,
 462 if any. Otherwise, it's either the host-name, domain-name, final
 463 directory name, or local host name. The path is everything
 464 besides the string before the initial '/' slash.
 465
 466 Return them as a list (name dir), with dir nil if none given."
 467   (let (name (path "") dir)
 468     (cond ((string= path-ish "") (setq dir multishell-primary-name))
 469           ((string-match "^\\*\\([^/]*\\)\\(/.*\\)\\*" path-ish)
 470            ;; We have a path, use it
 471            (let ((overt-name (match-string 1 path-ish)))
 472              (setq path (match-string 2 path-ish))
 473              (if (string= overt-name "") (setq overt-name nil))
 474              (if (string= path "") (setq path nil))
 475              (setq name
 476                    (multishell-bracket-asterisks
 477                     (or overt-name
 478                         (if (file-remote-p path)
 479                             (let ((vec (tramp-dissect-file-name path)))
 480                               (or (tramp-file-name-host vec)
 481                                   (tramp-file-name-domain vec)
 482                                   (tramp-file-name-localname vec)
 483                                   system-name))
 484                           (multishell-unbracket-asterisks
 485                            multishell-primary-name)))))))
 486           (t (setq name (multishell-bracket-asterisks path-ish))))
 487     (list name path)))
 488
 489 (defun multishell-bracket-asterisks (name)
 490   "Return a copy of name, ensuring it has an asterisk at the beginning and end."
 491   (if (not (string= (substring name 0 1) "*"))
 492       (setq name (concat "*" name)))
 493   (if (not (string= (substring name -1) "*"))
 494       (setq name (concat name "*")))
 495   name)
 496 (defun multishell-unbracket-asterisks (name)
 497   "Return a copy of name, removing asterisks, if any, at beginning and end."
 498   (if (string= (substring name 0 1) "*")
 499       (setq name (substring name 1)))
 500   (if (string= (substring name -1) "*")
 501       (setq name (substring name 0 -1)))
 502   name)
 503
 504 (defun multishell-start-shell-in-buffer (buffer-name path)
 505   "Ensure a shell is started, with name NAME and PATH."
 506   ;; We work around shell-mode's bracketing of the buffer name, and do
 507   ;; some tramp-mode hygiene for remote connections.
 508
 509   (let* ((buffer buffer-name)
 510          (prog (or explicit-shell-file-name
 511                    (getenv "ESHELL")
 512                    (getenv "SHELL")
 513                    "/bin/sh"))
 514          (name (file-name-nondirectory prog))
 515          (startfile (concat "~/.emacs_" name))
 516          (xargs-name (intern-soft (concat "explicit-" name "-args")))
 517          is-remote)
 518     (set-buffer buffer-name)
 519     (if (and path (not (string= path "")))
 520         (setq default-directory path))
 521     (setq is-remote (file-remote-p default-directory))
 522     (when (and is-remote
 523                (derived-mode-p 'shell-mode)
 524                (not (comint-check-proc (current-buffer))))
 525       ;; We're returning to an already established but disconnected remote
 526       ;; shell, tidy it:
 527       (tramp-cleanup-connection
 528        (tramp-dissect-file-name default-directory 'noexpand)
 529        'keep-debug 'keep-password))
 530     ;; (cd default-directory) will connect if remote:
 531     (when is-remote
 532       (message "Connecting to %s" default-directory))
 533     (condition-case err
 534         (cd default-directory)
 535       (error
 536        ;; Aargh. Need to isolate this tramp bug.
 537        (when (and (stringp (cadr err))
 538                   (string-equal (cadr err)
 539                                 "Selecting deleted buffer"))
 540          (signal (car err)
 541                  (list
 542                   (format "%s, %s (\"%s\")"
 543                           "Tramp shell can fail on empty (homedir) path"
 544                           "please try again with an explicit path"
 545                           (cadr err)))))))
 546     (setq buffer (set-buffer (apply 'make-comint
 547                                     (multishell-unbracket-asterisks buffer-name)
 548                                     prog
 549                                     (if (file-exists-p startfile)
 550                                         startfile)
 551                                     (if (and xargs-name
 552                                              (boundp xargs-name))
 553                                         (symbol-value xargs-name)
 554                                       '("-i")))))
 555     (shell-mode)))
 556
 557 (defun multishell-track-dirchange (name newpath)
 558   "Change multishell history entry to track current directory."
 559   (let* ((entries (multishell-history-entries name)))
 560     (dolist (entry entries)
 561       (let* ((name-path (multishell-split-entry-name-and-tramp entry))
 562              (name (car name-path))
 563              (path (cadr name-path)))
 564         (when path
 565           (let* ((is-remote (file-remote-p path))
 566                  (vec (and is-remote (tramp-dissect-file-name path nil)))
 567                  (localname (if is-remote
 568                                 (tramp-file-name-localname vec)
 569                               path))
 570                  (newlocalname
 571                   (replace-regexp-in-string (if (string= localname "")
 572                                                 "$"
 573                                               (regexp-quote localname))
 574                                             ;; REP
 575                                             newpath
 576                                             ;; STRING
 577                                             localname
 578                                             ;; FIXEDCASE
 579                                             t
 580                                             ;; LITERAL
 581                                             t
 582                                             ))
 583                  (newpath (if is-remote
 584                               (tramp-make-tramp-file-name (aref vec 0)
 585                                                           (aref vec 1)
 586                                                           (aref vec 2)
 587                                                           newlocalname
 588                                                           (aref vec 4))
 589                             newlocalname))
 590                  (newentry (concat name newpath))
 591                  (membership (member entry multishell-history)))
 592             (when membership
 593               (setcar membership newentry))))))))
 594 (defvar multishell-was-default-directory ()
 595   "Provide for tracking directory changes.")
 596 (make-variable-buffer-local 'multishell-was-default-directory)
 597 (defun multishell-post-command-business ()
 598   "Do multishell bookkeeping."
 599   ;; Update multishell-history with dir changes.
 600   (condition-case err
 601       (when (and multishell-history-entry-tracks-current-directory
 602                  (derived-mode-p 'shell-mode))
 603         (let ((curdir (if (file-remote-p default-directory)
 604                           (tramp-file-name-localname
 605                            (tramp-dissect-file-name default-directory))
 606                         default-directory)))
 607           (when (and multishell-was-default-directory
 608                      (not (string= curdir multishell-was-default-directory)))
 609             (multishell-track-dirchange (multishell-unbracket-asterisks
 610                                          (buffer-name))
 611                                         curdir))
 612           (setq multishell-was-default-directory curdir)))
 613     ;; To avoid disruption as a pervasive hook function, swallow all errors:
 614     (error nil)))
 615 (add-hook 'post-command-hook 'multishell-post-command-business)
 616
 617 (defun multishell-split-entry-name-and-tramp (entry)
 618   "Given multishell name/path ENTRY, return the separated name and path pair.
 619
 620 Returns nil for empty parts, rather than the empty string."
 621   (string-match "^\\([^/]*\\)\\(/?.*\\)?" entry)
 622   (let ((name (match-string 1 entry))
 623         (path (match-string 2 entry)))
 624     (and (string= name "") (setq name nil))
 625     (and (string= path "") (setq path nil))
 626     (list name path)))
 627
 628 (provide 'multishell)
 629
 630 ;;; multishell.el ends here