view lisp/code-process.el @ 5353:38e24b8be4ea

Improve the lexical scoping in #'block, #'return-from. lisp/ChangeLog addition: 2011-02-07 Aidan Kehoe <kehoea@parhasard.net> * bytecomp.el: * bytecomp.el (byte-compile-initial-macro-environment): Shadow `block', `return-from' here, we implement them differently when byte-compiling. * bytecomp.el (byte-compile-active-blocks): New. * bytecomp.el (byte-compile-block-1): New. * bytecomp.el (byte-compile-return-from-1): New. * bytecomp.el (return-from-1): New. * bytecomp.el (block-1): New. These are two aliases that exist to have their own associated byte-compile functions, which functions implement `block' and `return-from'. * cl-extra.el (cl-macroexpand-all): Fix a bug here when macros in the environment have been compiled. * cl-macs.el (block): * cl-macs.el (return): * cl-macs.el (return-from): Be more careful about lexical scope in these macros. * cl.el: * cl.el ('cl-block-wrapper): Removed. * cl.el ('cl-block-throw): Removed. These aren't needed in code generated by this XEmacs. They shouldn't be needed in code generated by XEmacs 21.4, but if it turns out the packages do need them, we can put them back. 2011-01-30 Mike Sperber <mike@xemacs.org> * font-lock.el (font-lock-fontify-pending-extents): Don't fail if `font-lock-mode' is unset, which can happen in the middle of `revert-buffer'. 2011-01-23 Aidan Kehoe <kehoea@parhasard.net> * cl-macs.el (delete): * cl-macs.el (delq): * cl-macs.el (remove): * cl-macs.el (remq): Don't use the compiler macro if these functions were given the wrong number of arguments, as happens in lisp-tests.el. * cl-seq.el (remove, remq): Removed. I added these to subr.el, and forgot to remove them from here. 2011-01-22 Aidan Kehoe <kehoea@parhasard.net> * bytecomp.el (byte-compile-setq, byte-compile-set): Remove kludge allowing keywords' values to be set, all the code that does that is gone. * cl-compat.el (elt-satisfies-test-p): * faces.el (set-face-parent): * faces.el (face-doc-string): * gtk-font-menu.el: * gtk-font-menu.el (gtk-reset-device-font-menus): * msw-font-menu.el: * msw-font-menu.el (mswindows-reset-device-font-menus): * package-get.el (package-get-installedp): * select.el (select-convert-from-image-data): * sound.el: * sound.el (load-sound-file): * x-font-menu.el (x-reset-device-font-menus-core): Don't quote keywords, they're self-quoting, and the win from backward-compatibility is sufficiently small now that the style problem overrides it. 2011-01-22 Aidan Kehoe <kehoea@parhasard.net> * cl-macs.el (block, return-from): Require that NAME be a symbol in these macros, as always documented in the #'block docstring and as required by Common Lisp. * descr-text.el (unidata-initialize-unihan-database): Correct the use of non-symbols in #'block and #'return-from in this function. 2011-01-15 Aidan Kehoe <kehoea@parhasard.net> * cl-extra.el (concatenate): Accept more complicated TYPEs in this function, handing the sequences over to #'coerce if we don't understand them here. * cl-macs.el (inline): Don't proclaim #'concatenate as inline, its compiler macro is more useful than doing that. 2011-01-11 Aidan Kehoe <kehoea@parhasard.net> * subr.el (delete, delq, remove, remq): Move #'remove, #'remq here, they don't belong in cl-seq.el; move #'delete, #'delq here from fns.c, implement them in terms of #'delete*, allowing support for sequences generally. * update-elc.el (do-autoload-commands): Use #'delete*, not #'delq here, now the latter's no longer dumped. * cl-macs.el (delete, delq): Add compiler macros transforming #'delete and #'delq to #'delete* calls. 2011-01-10 Aidan Kehoe <kehoea@parhasard.net> * dialog.el (make-dialog-box): Correct a misplaced parenthesis here, thank you Mats Lidell in 87zkr9gqrh.fsf@mail.contactor.se ! 2011-01-02 Aidan Kehoe <kehoea@parhasard.net> * dialog.el (make-dialog-box): * list-mode.el (display-completion-list): These functions used to use cl-parsing-keywords; change them to use defun* instead, fixing the build. (Not sure what led to me not including this change in d1b17a33450b!) 2011-01-02 Aidan Kehoe <kehoea@parhasard.net> * cl-macs.el (define-star-compiler-macros): Make sure the form has ITEM and LIST specified before attempting to change to calls with explicit tests; necessary for some tests in lisp-tests.el to compile correctly. (stable-union, stable-intersection): Add compiler macros for these functions, in the same way we do for most of the other functions in cl-seq.el. 2011-01-01 Aidan Kehoe <kehoea@parhasard.net> * cl-macs.el (dolist, dotimes, do-symbols, macrolet) (symbol-macrolet): Define these macros with defmacro* instead of parsing the argument list by hand, for the sake of style and readability; use backquote where appropriate, instead of calling #'list and and friends, for the same reason. 2010-12-30 Aidan Kehoe <kehoea@parhasard.net> * x-misc.el (device-x-display): Provide this function, documented in the Lispref for years, but not existing previously. Thank you Julian Bradfield, thank you Jeff Mincy. 2010-12-30 Aidan Kehoe <kehoea@parhasard.net> * cl-seq.el: Move the heavy lifting from this file to C. Dump the cl-parsing-keywords macro, but don't use defun* for the functions we define that do take keywords, dynamic scope lossage makes that not practical. * subr.el (sort, fillarray): Move these aliases here. (map-plist): #'nsublis is now built-in, but at this point #'eql isn't necessarily available as a test; use #'eq. * obsolete.el (cl-delete-duplicates): Make this available for old compiler macros and old code. (memql): Document that this is equivalent to #'member*, and worse. * cl.el (adjoin, subst): Removed. These are in C. 2010-12-30 Aidan Kehoe <kehoea@parhasard.net> * simple.el (assoc-ignore-case): Remove a duplicate definition of this function (it's already in subr.el). * iso8859-1.el (char-width): On non-Mule, make this function equivalent to that produced by (constantly 1), but preserve its docstring. * subr.el (subst-char-in-string): Define this in terms of #'substitute, #'nsubstitute. (string-width): Define this using #'reduce and #'char-width. (char-width): Give this a simpler definition, it makes far more sense to check for mule at load time and redefine, as we do in iso8859-1.el. (store-substring): Implement this in terms of #'replace, now #'replace is cheap. 2010-12-30 Aidan Kehoe <kehoea@parhasard.net> * update-elc.el (lisp-files-needed-for-byte-compilation) (lisp-files-needing-early-byte-compilation): cl-macs belongs in the former, not the latter, it is as fundamental as bytecomp.el. 2010-12-30 Aidan Kehoe <kehoea@parhasard.net> * cl.el: Provde the Common Lisp program-error, type-error as error symbols. This doesn't nearly go far enough for anyone using the Common Lisp errors. 2010-12-29 Aidan Kehoe <kehoea@parhasard.net> * cl-macs.el (delete-duplicates): If the form has an incorrect number of arguments, don't attempt a compiler macroexpansion. 2010-12-29 Aidan Kehoe <kehoea@parhasard.net> * cl-macs.el (cl-safe-expr-p): Forms that start with the symbol lambda are also safe. 2010-12-29 Aidan Kehoe <kehoea@parhasard.net> * cl-macs.el (= < > <= >=): For these functions' compiler macros, the optimisation is safe even if the first and the last arguments have side effects, since they're only used the once. 2010-12-29 Aidan Kehoe <kehoea@parhasard.net> * cl-macs.el (inline-side-effect-free-compiler-macros): Unroll a loop here at macro-expansion time, so these compiler macros are compiled. Use #'eql instead of #'eq in a couple of places for better style. 2010-12-29 Aidan Kehoe <kehoea@parhasard.net> * cl-extra.el (notany, notevery): Avoid some dynamic scope stupidity with local variable names in these functions, when they weren't prefixed with cl-; go into some more detail in the doc strings. 2010-12-29 Aidan Kehoe <kehoea@parhasard.net> * byte-optimize.el (side-effect-free-fns): #'remove, #'remq are free of side-effects. (side-effect-and-error-free-fns): Drop dot, dot-marker from the list. 2010-11-17 Aidan Kehoe <kehoea@parhasard.net> * cl-extra.el (coerce): In the argument list, name the first argument OBJECT, not X; the former name was always used in the doc string and is clearer. Handle vector type specifications which include the length of the target sequence, error if there's a mismatch. * cl-macs.el (cl-make-type-test): Handle type specifications starting with the symbol 'eql. 2010-11-14 Aidan Kehoe <kehoea@parhasard.net> * cl-macs.el (eql): Don't remove the byte-compile property of this symbol. That was necessary to override a bug in bytecomp.el where #'eql was confused with #'eq, which bug we no longer have. If neither expression is constant, don't attempt to handle the expression in this compiler macro, leave it to byte-compile-eql, which produces better code anyway. * bytecomp.el (eq): #'eql is not the function associated with the byte-eq byte code. (byte-compile-eql): Add an explicit compile method for this function, for cases where the cl-macs compiler macro hasn't reduced it to #'eq or #'equal. 2010-10-25 Aidan Kehoe <kehoea@parhasard.net> Add compiler macros and compilation sanity-checking for various functions that take keywords. * byte-optimize.el (side-effect-free-fns): #'symbol-value is side-effect free and not error free. * bytecomp.el (byte-compile-normal-call): Check keyword argument lists for sanity; store information about the positions where keyword arguments start using the new byte-compile-keyword-start property. * cl-macs.el (cl-const-expr-val): Take a new optional argument, cl-not-constant, defaulting to nil, in this function; return it if the expression is not constant. (cl-non-fixnum-number-p): Make this into a separate function, we want to pass it to #'every. (eql): Use it. (define-star-compiler-macros): Use the same code to generate the member*, assoc* and rassoc* compiler macros; special-case some code in #'add-to-list in subr.el. (remove, remq): Add compiler macros for these two functions, in preparation for #'remove being in C. (define-foo-if-compiler-macros): Transform (remove-if-not ...) calls to (remove ... :if-not) at compile time, which will be a real win once the latter is in C. (define-substitute-if-compiler-macros) (define-subst-if-compiler-macros): Similarly for these functions. (delete-duplicates): Change this compiler macro to use #'plists-equal; if we don't have information about the type of SEQUENCE at compile time, don't bother attempting to inline the call, the function will be in C soon enough. (equalp): Remove an old commented-out compiler macro for this, if we want to see it it's in version control. (subst-char-in-string): Transform this to a call to nsubstitute or nsubstitute, if that is appropriate. * cl.el (ldiff): Don't call setf here, this makes for a load-time dependency problem in cl-macs.el 2010-06-14 Stephen J. Turnbull <stephen@xemacs.org> * term/vt100.el: Refer to XEmacs, not GNU Emacs, in permissions. * term/bg-mouse.el: * term/sup-mouse.el: Put copyright notice in canonical "Copyright DATE AUTHOR" form. Refer to XEmacs, not GNU Emacs, in permissions. * site-load.el: Add permission boilerplate. * mule/canna-leim.el: * alist.el: Refer to XEmacs, not APEL/this program, in permissions. * mule/canna-leim.el: Remove my copyright, I've assigned it to the FSF. 2010-06-14 Stephen J. Turnbull <stephen@xemacs.org> * gtk.el: * gtk-widget-accessors.el: * gtk-package.el: * gtk-marshal.el: * gtk-compose.el: * gnome.el: Add copyright notice based on internal evidence. 2010-06-14 Stephen J. Turnbull <stephen@xemacs.org> * easymenu.el: Add reference to COPYING to permission notice. * gutter.el: * gutter-items.el: * menubar-items.el: Fix typo "Xmacs" in permissions notice. 2010-06-14 Stephen J. Turnbull <stephen@xemacs.org> * auto-save.el: * font.el: * fontconfig.el: * mule/kinsoku.el: Add "part of XEmacs" text to permission notice. 2010-10-14 Aidan Kehoe <kehoea@parhasard.net> * byte-optimize.el (side-effect-free-fns): * cl-macs.el (remf, getf): * cl-extra.el (tailp, cl-set-getf, cl-do-remf): * cl.el (ldiff, endp): Tighten up Common Lisp compatibility for #'ldiff, #'endp, #'tailp; add circularity checking for the first two. #'cl-set-getf and #'cl-do-remf were Lisp implementations of #'plist-put and #'plist-remprop; change the names to aliases, changes the macros that use them to using #'plist-put and #'plist-remprop directly. 2010-10-12 Aidan Kehoe <kehoea@parhasard.net> * abbrev.el (fundamental-mode-abbrev-table, global-abbrev-table): Create both these abbrev tables using the usual #'define-abbrev-table calls, rather than attempting to special-case them. * cl-extra.el: Force cl-macs to be loaded here, if cl-extra.el is being loaded interpreted. Previously other, later files would redundantly call (load "cl-macs") when interpreted, it's more reasonable to do it here, once. * cmdloop.el (read-quoted-char-radix): Use defcustom here, we don't have any dump-order dependencies that would prevent that. * custom.el (eval-when-compile): Don't load cl-macs when interpreted or when byte-compiling, rely on cl-extra.el in the former case and the appropriate entry in bytecomp-load-hook in the latter. Get rid of custom-declare-variable-list, we have no dump-time dependencies that would require it. * faces.el (eval-when-compile): Don't load cl-macs when interpreted or when byte-compiling. * packages.el: Remove some inaccurate comments. * post-gc.el (cleanup-simple-finalizers): Use #'delete-if-not here, now the order of preloaded-file-list has been changed to make it available. * subr.el (custom-declare-variable-list): Remove. No need for it. Also remove a stub define-abbrev-table from this file, given the current order of preloaded-file-list there's no need for it. 2010-10-10 Aidan Kehoe <kehoea@parhasard.net> * bytecomp.el (byte-compile-constp) Forms quoted with FUNCTION are also constant. (byte-compile-initial-macro-environment): In #'the, if FORM is constant and does not match TYPE, warn at byte-compile time. 2010-10-10 Aidan Kehoe <kehoea@parhasard.net> * backquote.el (bq-vector-contents, bq-list*): Remove; the former is equivalent to (append VECTOR nil), the latter to (list* ...). (bq-process-2): Use (append VECTOR nil) instead of using #'bq-vector-contents to convert to a list. (bq-process-1): Now we use list* instead of bq-list * subr.el (list*): Moved from cl.el, since it is now required to be available the first time a backquoted form is encountered. * cl.el (list*): Move to subr.el. 2010-09-16 Aidan Kehoe <kehoea@parhasard.net> * test-harness.el (Check-Message): Add an omitted comma here, thank you the buildbot. 2010-09-16 Aidan Kehoe <kehoea@parhasard.net> * hash-table.el (hash-table-key-list, hash-table-value-list) (hash-table-key-value-alist, hash-table-key-value-plist): Remove some useless #'nreverse calls in these files; our hash tables have no order, it's not helpful to pretend they do. * behavior.el (read-behavior): Do the same in this file, in some code evidently copied from hash-table.el. 2010-09-16 Aidan Kehoe <kehoea@parhasard.net> * info.el (Info-insert-dir): * format.el (format-deannotate-region): * files.el (cd, save-buffers-kill-emacs): Use #'some, #'every and related functions for applying boolean operations to lists, instead of rolling our own ones that cons and don't short-circuit. 2010-09-16 Aidan Kehoe <kehoea@parhasard.net> * bytecomp.el (byte-compile-initial-macro-environment): * cl-macs.el (the): Rephrase the docstring, make its implementation when compiling files a little nicer. 2010-09-16 Aidan Kehoe <kehoea@parhasard.net> * descr-text.el (unidata-initialize-unicodedata-database) (unidata-initialize-unihan-database, describe-char-unicode-data) (describe-char-unicode-data): Wrap calls to the database functions with (with-fboundp ...), avoiding byte compile warnings on builds without support for the database functions. (describe-char): (reduce #'max ...), not (apply #'max ...), no need to cons needlessly. (describe-char): Remove a redundant lambda wrapping #'extent-properties. (describe-char-unicode-data): Call #'nsubst when replacing "" with nil in the result of #'split-string, instead of consing inside mapcar. 2010-09-16 Aidan Kehoe <kehoea@parhasard.net> * x-faces.el (x-available-font-sizes): * specifier.el (let-specifier): * package-ui.el (pui-add-required-packages): * msw-faces.el (mswindows-available-font-sizes): * modeline.el (modeline-minor-mode-menu): * minibuf.el (minibuf-directory-files): Replace the O2N (delq nil (mapcar (lambda (W) (and X Y)) Z)) with the ON (mapcan (lambda (W) (and X (list Y))) Z) in these files. 2010-09-16 Aidan Kehoe <kehoea@parhasard.net> * cl-macs.el (= < > <= >=): When these functions are handed more than two arguments, and those arguments have no side effects, transform to a series of two argument calls, avoiding funcall in the byte-compiled code. * mule/mule-cmds.el (finish-set-language-environment): Take advantage of this change in a function called 256 times at startup. 2010-09-16 Aidan Kehoe <kehoea@parhasard.net> * bytecomp.el (byte-compile-function-form, byte-compile-quote) (byte-compile-quote-form): Warn at compile time, and error at runtime, if a (quote ...) or a (function ...) form attempts to quote more than one object. 2010-09-16 Aidan Kehoe <kehoea@parhasard.net> * byte-optimize.el (byte-optimize-apply): Transform (apply 'nconc (mapcar ...)) to (mapcan ...); warn about use of the first idiom. * update-elc.el (do-autoload-commands): * packages.el (packages-find-package-library-path): * frame.el (frame-list): * extents.el (extent-descendants): * etags.el (buffer-tag-table-files): * dumped-lisp.el (preloaded-file-list): * device.el (device-list): * bytecomp-runtime.el (proclaim-inline, proclaim-notinline) Use #'mapcan, not (apply #'nconc (mapcar ...) in all these files. * bytecomp-runtime.el (eval-when-compile, eval-and-compile): In passing, mention that these macros also evaluate the body when interpreted. tests/ChangeLog addition: 2011-02-07 Aidan Kehoe <kehoea@parhasard.net> * automated/lisp-tests.el: Test lexical scope for `block', `return-from'; add a Known-Bug-Expect-Failure for a contorted example that fails when byte-compiled.
author Aidan Kehoe <kehoea@parhasard.net>
date Mon, 07 Feb 2011 12:01:24 +0000
parents 0b060ef35789
children 91b3aa59f49b
line wrap: on
line source

;;; code-process.el --- Process coding functions for XEmacs.

;; Copyright (C) 1985-1987, 1993, 1994, 1997 Free Software Foundation, Inc.
;; Copyright (C) 1995, 2000, 2002 Ben Wing
;; Copyright (C) 1997 MORIOKA Tomohiko

;; Author: Ben Wing
;;         MORIOKA Tomohiko
;; Maintainer: XEmacs Development Team
;; Keywords: mule, multilingual, coding system, process

;; This file is part of XEmacs.

;; This file is very similar to code-process.el

;; XEmacs is free software; you can redistribute it and/or modify it
;; under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.

;; XEmacs is distributed in the hope that it will be useful, but
;; WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
;; General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with XEmacs; see the file COPYING.  If not, write to the Free
;; Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
;; 02111-1307, USA.

;;; Code:

(defvar process-coding-system-alist nil
  "Alist to decide a coding system to use for a process I/O operation.
The format is ((PATTERN . VAL) ...),
where PATTERN is a regular expression matching a program name,
VAL is a coding system, a cons of coding systems, or a function symbol.
If VAL is a coding system, it is used for both decoding what received
from the program and encoding what sent to the program.
If VAL is a cons of coding systems, the car part is used for decoding,
and the cdr part is used for encoding.
If VAL is a function symbol, it is called with two arguments, a symbol
indicating the operation being performed (one of `start-process',
`call-process', `open-network-stream', or `open-multicast-group') and the
program name.  The function must return a coding system or a cons of
coding systems which are used as above.")

(defun call-process (program &optional infile buffer displayp &rest args)
  "Call PROGRAM synchronously in separate process.

The program's input comes from file INFILE (nil means `/dev/null').
XEmacs feature: INFILE can also be a list of (BUFFER [START [END]]), i.e.
a list of one to three elements, consisting of a buffer and optionally
a start position or start and end position.  In this case, input comes
from the buffer, starting from START (defaults to the beginning of the
buffer) and ending at END (defaults to the end of the buffer).

Insert output in BUFFER before point; t means current buffer;
 nil for BUFFER means discard it; 0 means discard and don't wait.
If BUFFER is a string, then find or create a buffer with that name,
then insert the output in that buffer, before point.
BUFFER can also have the form (REAL-BUFFER STDERR-FILE); in that case,
REAL-BUFFER says what to do with standard output, as above,
while STDERR-FILE says what to do with standard error in the child.
STDERR-FILE may be nil (discard standard error output),
t (mix it with ordinary output), a file name string, or (XEmacs feature)
a buffer object.  If STDERR-FILE is a buffer object (but not the name of
a buffer, since that would be interpreted as a file), the standard error
output will be inserted into the buffer before point.

Fourth arg DISPLAY non-nil means redisplay buffer as output is inserted.
Remaining arguments are strings passed as command arguments to PROGRAM.

If BUFFER is 0, returns immediately with value nil.
Otherwise waits for PROGRAM to terminate and returns a numeric exit status
or a signal description string.  If you quit, the process is first killed
with SIGINT, then with SIGKILL if you quit again before the process exits.

If INFILE is a file, we transfer its exact contents to the process without
any encoding/decoding. (#### This policy might change.)

Otherwise, the read/write coding systems used for process I/O on the
process are determined as follows:

1. `coding-system-for-read', `coding-system-for-write', if non-nil.
      (Intended as a temporary overriding mechanism for use by Lisp
      code.)
2. The matching value for the process name from `process-coding-system-alist',
      if any, and if non-nil.  The value may be either a single coding
      system, used for both read and write; or a cons of read/write; or a
      function, called to get one of the other two values.
3. For writing: If a buffer was given in INFILE, the value of
      `buffer-file-coding-system' in that buffer.
   For reading: if a buffer was given in BUFFER, the value of
      `buffer-file-coding-system-for-read' in that buffer.
4. The value of `default-process-coding-system', which should be a cons
      of read/write coding systems, if the values are non-nil.
5. The coding system `undecided' for read, and `raw-text' for write.

Note that the processes of determining the read and write coding systems
proceed essentially independently one from the other, as in `start-process'."
  (let (cs-r cs-w)
    (let (ret)
      (catch 'found
	(let ((alist process-coding-system-alist)
	      (case-fold-search nil))
	  (while alist
	    (if (string-match (car (car alist)) program)
		(throw 'found (setq ret (cdr (car alist)))))
	    (setq alist (cdr alist))
	    )))
      (if (functionp ret)
	  (setq ret (funcall ret 'call-process program)))
      (cond ((consp ret)
	     (setq cs-r (car ret)
		   cs-w (cdr ret)))
	    ((and ret (find-coding-system ret))
	     (setq cs-r ret
		   cs-w ret))))
    (let ((coding-system-for-read
	   (or coding-system-for-read cs-r
	       (let ((thebuf (if (consp buffer) (car buffer) buffer)))
		 (and (or (bufferp thebuf) (stringp thebuf))
		      (get-buffer thebuf)
		      (symbol-value-in-buffer
		       'buffer-file-coding-system-for-read (get-buffer thebuf))))
	       (car default-process-coding-system)
	       'undecided))
	  (coding-system-for-write
	   (or coding-system-for-write cs-w
	       (and (consp infile)
		    (symbol-value-in-buffer
		     'buffer-file-coding-system
		     (get-buffer (car infile))))
	       (cdr default-process-coding-system)
	       'raw-text)))
      (apply 'call-process-internal program infile buffer displayp args))))

(defun call-process-region (start end program
				  &optional deletep buffer displayp
				  &rest args)
  "Send text from START to END to a synchronous process running PROGRAM.
Delete the text if fourth arg DELETEP is non-nil.

Insert output in BUFFER before point; t means current buffer;
 nil for BUFFER means discard it; 0 means discard and don't wait.
If BUFFER is a string, then find or create a buffer with that name,
then insert the output in that buffer, before point.
BUFFER can also have the form (REAL-BUFFER STDERR-FILE); in that case,
REAL-BUFFER says what to do with standard output, as above,
while STDERR-FILE says what to do with standard error in the child.
STDERR-FILE may be nil (discard standard error output),
t (mix it with ordinary output), a file name string, or (XEmacs feature)
a buffer object.  If STDERR-FILE is a buffer object (but not the name of
a buffer, since that would be interpreted as a file), the standard error
output will be inserted into the buffer before point.

Sixth arg DISPLAYP non-nil means redisplay buffer as output is inserted.
Remaining args are passed to PROGRAM at startup as command args.

If BUFFER is 0, returns immediately with value nil.
Otherwise waits for PROGRAM to terminate and returns a numeric exit status
or a signal description string.  If you quit, the process is first killed
with SIGINT, then with SIGKILL if you quit again before the process exits.

The read/write coding systems used for process I/O on the process are
the same as for `call-process'."

  ;; We can't delete the region before feeding it to `call-process', so we
  ;; take care not to delete the insertion when we delete the region.  START
  ;; and END may not be markers; copy them.  (point) will end up after the
  ;; insertion.  A copy of (point) tracks the beginning of the insertion.

  (let ((s (and deletep (copy-marker start)))         ;  Only YOU can
	(e (and deletep (copy-marker end t)))         ;     prevent
	(p (and deletep (copy-marker (point))))       ; excess consing!
	(retval
	 (apply #'call-process program (list (current-buffer) start end)
		buffer displayp args)))
    (when deletep
      (if (<= s p e)
	  ;; region was split by insertion
	  ;; the order checks are gilt lilies
	  (progn (when (< (point) e) (delete-region (point) e))
		 (when (< s p) (delete-region s p)))
	;; insertion was outside of region
	(delete-region s e)))
    retval))

(defun start-process (name buffer program &rest program-args)
  "Start a program in a subprocess.  Return the process object for it.
NAME is name for process.  It is modified if necessary to make it unique.
BUFFER is the buffer or (buffer-name) to associate with the process.
 Process output goes at end of that buffer, unless you specify
 an output stream or filter function to handle the output.
 BUFFER may be also nil, meaning that this process is not associated
 with any buffer.
BUFFER can also have the form (REAL-BUFFER STDERR-BUFFER); in that case,
 REAL-BUFFER says what to do with standard output, as above,
 while STDERR-BUFFER says what to do with standard error in the child.
 STDERR-BUFFER may be nil (discard standard error output, unless a stderr
 filter is set).  Note that if you do not use this form at process creation,
 stdout and stderr will be mixed in the output buffer, and this cannot be
 changed, even by setting a stderr filter.
Third arg is program file name.  It is searched for as in the shell.
Remaining arguments are strings to give program as arguments.

The read/write coding systems used for process I/O on the process are
determined as follows:

1. `coding-system-for-read', `coding-system-for-write', if non-nil.
      (Intended as a temporary overriding mechanism for use by Lisp
      code.)
2. The matching value for the process name from `process-coding-system-alist',
      if any, and if non-nil.  The value may be either a single coding
      system, used for both read and write; or a cons of read/write; or a
      function, called to get one of the other two values.
3. The value of `default-process-coding-system', which should be a cons
      of read/write coding systems, if the values are non-nil.
4. The coding system `undecided' for read, and `raw-text' for write.

Note that the processes of determining the read and write coding systems
proceed essentially independently one from the other.  For example, a value
determined from `process-coding-system-alist' might specify a read coding
system but not a write coding system, in which the read coding system is as
specified and the write coding system comes from proceeding to step 3 (and
looking in `default-process-coding-system').

You can change the coding systems later on using
`set-process-coding-system', `set-process-input-coding-system', or
`set-process-output-coding-system'.

See also `set-process-filter' and `set-process-stderr-filter'."
  (let (cs-r cs-w)
    (let (ret)
      (catch 'found
	(let ((alist process-coding-system-alist)
	      (case-fold-search nil))
	  (while alist
	    (if (string-match (car (car alist)) program)
		(throw 'found (setq ret (cdr (car alist)))))
	    (setq alist (cdr alist))
	    )))
      (if (functionp ret)
	  (setq ret (funcall ret 'start-process program)))
      (cond ((consp ret)
	     (setq cs-r (car ret)
		   cs-w (cdr ret)))
	    ((and ret (find-coding-system ret))
	     (setq cs-r ret
		   cs-w ret))))
    (let ((coding-system-for-read
	   (or coding-system-for-read cs-r
	       (car default-process-coding-system) 'undecided))
	  (coding-system-for-write
	   (or coding-system-for-write cs-w
	       (cdr default-process-coding-system) 'raw-text)))
      (apply 'start-process-internal name buffer program program-args)
      )))

(defvar network-coding-system-alist nil
  "Alist to decide a coding system to use for a network I/O operation.
The format is ((PATTERN . VAL) ...),
where PATTERN is a regular expression matching a network service name
or is a port number to connect to,
VAL is a coding system, a cons of coding systems, or a function symbol.
If VAL is a coding system, it is used for both decoding what received
from the network stream and encoding what sent to the network stream.
If VAL is a cons of coding systems, the car part is used for decoding,
and the cdr part is used for encoding.
If VAL is a function symbol, the function must return a coding system
or a cons of coding systems which are used as above.

See also the function `find-operation-coding-system'.")

(defun open-network-stream (name buffer host service &optional protocol)
  "Open a TCP connection for a service to a host.
Return a process object to represent the connection.
Input and output work as for subprocesses; `delete-process' closes it.
NAME is name for process.  It is modified if necessary to make it unique.
BUFFER is the buffer (or buffer-name) to associate with the process.
 Process output goes at end of that buffer, unless you specify
 an output stream or filter function to handle the output.
 BUFFER may be also nil, meaning that this process is not associated
 with any buffer.
Third arg is name of the host to connect to, or its IP address.
Fourth arg SERVICE is name of the service desired, or an integer
 specifying a port number to connect to.
Fifth argument PROTOCOL is a network protocol.  Currently 'tcp
 (Transmission Control Protocol) and 'udp (User Datagram Protocol) are
 supported.  When omitted, 'tcp is assumed.

Output via `process-send-string' and input via buffer or filter (see
`set-process-filter') are stream-oriented.  That means UDP datagrams are
not guaranteed to be sent and received in discrete packets. (But small
datagrams around 500 bytes that are not truncated by `process-send-string'
are usually fine.)  Note further that UDP protocol does not guard against 
lost packets.

The read/write coding systems used for process I/O on the process are
determined as follows:

1. `coding-system-for-read', `coding-system-for-write', if non-nil.
      (Intended as a temporary overriding mechanism for use by Lisp
      code.)
2. The matching value for the service from `network-coding-system-alist',
      if any, and if non-nil.  The value may be either a single coding
      system, used for both read and write; or a cons of read/write; or a
      function, called to get one of the other two values.
3. The value of `default-network-coding-system', which should be a cons
      of read/write coding systems, if the values are non-nil.
4. The coding system `undecided' for read, and `raw-text' for write.

Note that the processes of determining the read and write coding systems
proceed essentially independently one from the other, as in `start-process'.

You can change the coding systems later on using
`set-process-coding-system', `set-process-input-coding-system', or
`set-process-output-coding-system'."
  (let (cs-r cs-w)
    (let (ret)
      (catch 'found
	(let ((alist network-coding-system-alist)
	      (case-fold-search nil)
	      pattern)
	  (while alist
	    (setq pattern (car (car alist)))
	    (and
	     (cond ((numberp pattern)
		    (and (numberp service)
			 (eq pattern service)))
		   ((stringp pattern)
		    (or (and (stringp service)
			     (string-match pattern service))
			(and (numberp service)
			     (string-match pattern
					   (number-to-string service))))))
	     (throw 'found (setq ret (cdr (car alist)))))
	    (setq alist (cdr alist))
	    )))
      (if (functionp ret)
	  (setq ret (funcall ret 'open-network-stream service)))
      (cond ((consp ret)
	     (setq cs-r (car ret)
		   cs-w (cdr ret)))
	    ((and ret (find-coding-system ret))
	     (setq cs-r ret
		   cs-w ret))))
    (let ((coding-system-for-read
	   (or coding-system-for-read cs-r
	       (car default-network-coding-system)
	       'undecided))
	  (coding-system-for-write
	   (or coding-system-for-write cs-w
	       (cdr default-network-coding-system)
	       'raw-text)))
      (open-network-stream-internal name buffer host service protocol))))

(defun set-buffer-process-coding-system (decoding encoding)
  "Set coding systems for the process associated with the current buffer.
DECODING is the coding system to be used to decode input from the process,
ENCODING is the coding system to be used to encode output to the process.

For a list of possible values of CODING-SYSTEM, use \\[coding-system-list]."
  (interactive
   "zCoding-system for process input: \nzCoding-system for process output: ")
  (let ((proc (get-buffer-process (current-buffer))))
    (if (null proc)
	(error "no process")
      (get-coding-system decoding)
      (get-coding-system encoding)
      (set-process-coding-system proc decoding encoding)))
  (force-mode-line-update))

;;; code-process.el ends here