This is Info file ../info/xemacs-faq.info, produced by Makeinfo version
1.68 from the input file xemacs-faq.texi.


File: xemacs-faq.info,  Node: Q5.1.7,  Next: Q5.1.8,  Prev: Q5.1.6,  Up: Miscellaneous

I like the the `do' form of cl, does it slow things down?
=========================================================

   It shouldn't.  Here is what Dave Gillespie has to say about cl.el
performance:

     Many of the advanced features of this package, such as `defun*',
     `loop', and `setf', are implemented as Lisp macros.  In
     byte-compiled code, these complex notations will be expanded into
     equivalent Lisp code which is simple and efficient.  For example,
     the forms

          (incf i n)
          (push x (car p))

     are expanded at compile-time to the Lisp forms

          (setq i (+ i n))
          (setcar p (cons x (car p)))

     which are the most efficient ways of doing these respective
     operations in Lisp.  Thus, there is no performance penalty for
     using the more readable `incf' and `push' forms in your compiled
     code.

     *Interpreted* code, on the other hand, must expand these macros
     every time they are executed.  For this reason it is strongly
     recommended that code making heavy use of macros be compiled.  (The
     features labelled "Special Form" instead of "Function" in this
     manual are macros.)  A loop using `incf' a hundred times will
     execute considerably faster if compiled, and will also
     garbage-collect less because the macro expansion will not have to
     be generated, used, and thrown away a hundred times.

     You can find out how a macro expands by using the `cl-prettyexpand'
     function.


File: xemacs-faq.info,  Node: Q5.1.8,  Next: Q5.1.9,  Prev: Q5.1.7,  Up: Miscellaneous

I like recursion, does it slow things down?
===========================================

   Yes.  Emacs byte-compiler cannot do much to optimize recursion.  But
think well whether this is a real concern in Emacs.  Much of the Emacs
slowness comes from internal mechanisms such as redisplay, or from the
fact that it is an interpreter.

   Please try not to make your code much uglier to gain a very small
speed gain.  It's not usually worth it.


File: xemacs-faq.info,  Node: Q5.1.9,  Next: Q5.1.10,  Prev: Q5.1.8,  Up: Miscellaneous

How do I put a glyph as annotation in a buffer?
===============================================

   Here is a solution that will insert the glyph annotation at the
beginning of buffer:

     (make-annotation (make-glyph '([FORMAT :file FILE]
                                    [string :data "fallback-text"]))
                      (point-min)
                      'text
                      (current-buffer))

   Replace `FORMAT' with an unquoted symbol representing the format of
the image (e.g. `xpm', `xbm', `gif', `jpeg', etc.)  Instead of `FILE',
use the image file name (e.g.
`/usr/local/lib/xemacs-20.2/etc/recycle.xpm').

   You can turn this to a function (that optionally prompts you for a
file name), and inserts the glyph at `(point)' instead of `(point-min)'.


File: xemacs-faq.info,  Node: Q5.1.10,  Next: Q5.2.1,  Prev: Q5.1.9,  Up: Miscellaneous

`map-extents' won't traverse all of my extents!
===============================================

   I tried to use `map-extents' to do an operation on all the extents
in a region.  However, it seems to quit after processing a random number
of extents.  Is it buggy?

   No.  The documentation of `map-extents' states that it will iterate
across the extents as long as FUNCTION returns `nil'.  Unexperienced
programmers often forget to return `nil' explicitly, which results in
buggy code.  For instance, the following code is supposed to delete all
the extents in a buffer, and issue as many `fubar!' messages.

     (map-extents (lambda (ext ignore)
                    (delete-extent ext)
                    (message "fubar!")))

   Instead, it will delete only the first extent, and stop right there -
because `message' will return a non-nil value.  The correct code is:

     (map-extents (lambda (ext ignore)
                    (delete-extent ext)
                    (message "fubar!")
                    nil))


File: xemacs-faq.info,  Node: Q5.2.1,  Next: Q5.2.2,  Prev: Q5.1.10,  Up: Miscellaneous

How do I turn off the sound?
============================

   Add the following line to your `.emacs':

     (setq bell-volume 0)
     (setq sound-alist nil)

   That will make your XEmacs totally silent - even the default ding
sound (TTY beep on TTY-s) will be gone.


File: xemacs-faq.info,  Node: Q5.2.2,  Next: Q5.2.3,  Prev: Q5.2.1,  Up: Miscellaneous

How do I get funky sounds instead of a boring beep?
===================================================

   Make sure your XEmacs was compiled with sound support, and then put
this in your `.emacs':

     (load-default-sounds)

   The sound support in XEmacs 19.14 was greatly improved over previous
versions.


File: xemacs-faq.info,  Node: Q5.2.3,  Next: Q5.2.4,  Prev: Q5.2.2,  Up: Miscellaneous

What's NAS, how do I get it?
============================

   *Note Q2.0.3:: for an explanation of the "Network Audio System".


File: xemacs-faq.info,  Node: Q5.2.4,  Next: Q5.3.1,  Prev: Q5.2.3,  Up: Miscellaneous

Sunsite sounds don't play.
==========================

   I'm having some trouble with sounds I've downloaded from sunsite.
They play when I run them through `showaudio' or cat them directly to
`/dev/audio', but XEmacs refuses to play them.

   Markus Gutschke <gutschk@uni-muenster.de> writes:

     [Many of] These files have an (erroneous) 24byte header that tells
     about the format that they have been recorded in. If you cat them
     to `/dev/audio', the header will be ignored and the default
     behavior for /dev/audio will be used. This happens to be 8kHz
     uLaw. It is probably possible to fix the header by piping through
     `sox' and passing explicit parameters for specifying the sampling
     format; you then need to perform a 'null' conversion from SunAudio
     to SunAudio.


File: xemacs-faq.info,  Node: Q5.3.1,  Next: Q5.3.2,  Prev: Q5.2.4,  Up: Miscellaneous

How do you make XEmacs indent CL if-clauses correctly?
======================================================

   I'd like XEmacs to indent all the clauses of a Common Lisp `if' the
same amount instead of indenting the 3rd clause differently from the
first two.

   One way is to add, to `.emacs':

     (put 'if 'lisp-indent-function nil)

   However, note that the package `cl-indent.el' that comes with XEmacs
sets up this kind of indentation by default.  `cl-indent' also knows
about many other CL-specific forms.  To use `cl-indent', one can do
this:

     (load "cl-indent")
     (setq lisp-indent-function (function common-lisp-indent-function))

   One can also customize `cl-indent.el' so it mimics the default `if'
indentation `then' indented more than the `else'.  Here's how:

     (put 'if 'common-lisp-indent-function '(nil nil &body))

   Also, a new version (1.2) of `cl-indent.el' was posted to
comp.emacs.xemacs on 12/9/94.  This version includes more documentation
than previous versions.  This may prove useful if you need to customize
any indent-functions.


File: xemacs-faq.info,  Node: Q5.3.2,  Next: Q5.3.3,  Prev: Q5.3.1,  Up: Miscellaneous

Fontifying hang when editing a postscript file.
===============================================

   When I try to edit a postscript file it gets stuck saying:
`fontifying 'filename' (regexps....)' and it just sits there.  If I
press `C-c' in the window where XEmacs was started, it suddenly becomes
alive again.

   This was caused by a bug in the Postscript font-lock regular
expressions.  It was fixed in 19.13.  For earlier versions of XEmacs,
have a look at your `.emacs' file.  You will probably have a line like:

     (add-hook 'postscript-mode-hook	'turn-on-font-lock)

   Take it out, restart XEmacs, and it won't try to fontify your
postscript files anymore.


File: xemacs-faq.info,  Node: Q5.3.3,  Next: Q5.3.4,  Prev: Q5.3.2,  Up: Miscellaneous

How can I print WYSIWYG a font-locked buffer?
=============================================

   Font-lock looks nice.  How can I print (WYSIWYG) the highlighted
document?

   The package `ps-print.el', which is now included with XEmacs,
provides the ability to do this.  The source code contains complete
instructions on its use, in
`<xemacs_src_root>/lisp/packages/ps-print.el'.


File: xemacs-faq.info,  Node: Q5.3.4,  Next: Q5.3.5,  Prev: Q5.3.3,  Up: Miscellaneous

Getting `M-x lpr' to work with postscript printer.
==================================================

   My printer is a Postscript printer and `lpr' only works for
Postscript files, so how do I get `M-x lpr-region' and `M-x lpr-buffer'
to work?

   Put something like this in your `.emacs':

     (setq lpr-command "a2ps")
     (setq lpr-switches '("-p" "-1"))

   If you don't use a2ps to convert ASCII to postscript (why not, it's
free?), replace with the command you do use.  Note also that some
versions of a2ps require a `-Pprinter' to ensure spooling.


File: xemacs-faq.info,  Node: Q5.3.5,  Next: Q5.3.6,  Prev: Q5.3.4,  Up: Miscellaneous

How do I specify the paths that XEmacs uses for finding files?
==============================================================

   You can specify what paths to use by using a number of different
flags when running configure.  See the section MAKE VARIABLES in the
top-level file INSTALL in the XEmacs distribution for a listing of
those flags.

   Most of the time, however, the simplest fix is: *do not* specify
paths as you might for GNU Emacs.  XEmacs can generally determine the
necessary paths dynamically at run time.  The only path that generally
needs to be specified is the root directory to install into.  That can
be specified by passing the `--prefix' flag to configure.  For a
description of the XEmacs install tree, please consult the `NEWS' file.


File: xemacs-faq.info,  Node: Q5.3.6,  Next: Q5.3.7,  Prev: Q5.3.5,  Up: Miscellaneous

[This question intentionally left blank]
========================================

   Obsolete question, left blank to avoid renumbering.


File: xemacs-faq.info,  Node: Q5.3.7,  Next: Q5.3.8,  Prev: Q5.3.6,  Up: Miscellaneous

Can I have the end of the buffer delimited in some way?
=======================================================

   Say, with: `[END]'?

   Try this:

     (let ((ext (make-extent (point-min) (point-max))))
       (set-extent-property ext 'start-closed t)
       (set-extent-property ext 'end-closed t)
       (set-extent-property ext 'detachable nil)
       (set-extent-end-glyph ext (make-glyph [string :data "[END]"])))

   Since this is XEmacs, you can specify an icon to be shown on
window-system devices.  To do so, change the `make-glyph' call to
something like this:

     (make-glyph '([xpm :file "~/something.xpm"]
                   [string :data "[END]"]))

   You can inline the XPM definition yourself by specifying `:data'
instead of `:file'.  Here is such a full-featured version that works on
both X and TTY devices:

     (let ((ext (make-extent (point-min) (point-max))))
       (set-extent-property ext 'start-closed t)
       (set-extent-property ext 'end-closed t)
       (set-extent-property ext 'detachable nil)
       (set-extent-end-glyph ext (make-glyph '([xpm :data "\
     /* XPM */
     static char* eye = {
     \"20 11 7 2\",
     \"__ c None\"
     \"_` c #7f7f7f\",
     \"_a c #fefefe\",
     \"_b c #7f0000\",
     \"_c c #fefe00\",
     \"_d c #fe0000\",
     \"_e c #bfbfbf\",
     \"___________`_`_`___b_b_b_b_________`____\",
     \"_________`_`_`___b_c_c_c_b_b____________\",
     \"_____`_`_`_e___b_b_c_c_c___b___b_______`\",
     \"___`_`_e_a___b_b_d___b___b___b___b______\",
     \"_`_`_e_a_e___b_b_d_b___b___b___b___b____\",
     \"_`_`_a_e_a___b_b_d___b___b___b___b___b__\",
     \"_`_`_e_a_e___b_b_d_b___b___b___b___b_b__\",
     \"___`_`_e_a___b_b_b_d_c___b___b___d_b____\",
     \"_____`_`_e_e___b_b_b_d_c___b_b_d_b______\",
     \"_`_____`_`_`_`___b_b_b_d_d_d_d_b________\",
     \"___`_____`_`_`_`___b_b_b_b_b_b__________\",
     } ;"]
                                               [string :data "[END]"]))))

   Note that you might want to make this a function, and put it to a
hook.  We leave that as an exercise for the reader.


File: xemacs-faq.info,  Node: Q5.3.8,  Next: Q5.3.9,  Prev: Q5.3.7,  Up: Miscellaneous

How do I insert today's date into a buffer?
===========================================

   Like this:

     (insert (current-time-string))


File: xemacs-faq.info,  Node: Q5.3.9,  Next: Q5.3.10,  Prev: Q5.3.8,  Up: Miscellaneous

Are only certain syntactic character classes available for abbrevs?
===================================================================

   Markus Gutschke <gutschk@uni-muenster.de> writes:

     Yes, abbrevs only expands word-syntax strings. While XEmacs does
     not prevent you from defining (e.g. with `C-x a g' or `C-x a l')
     abbrevs that contain special characters, it will refuse to expand
     them. So you need to ensure, that the abbreviation contains
     letters and digits only. This means that `xd', `d5', and `5d' are
     valid abbrevs, but `&d', and `x d' are not.

     If this sounds confusing to you, (re-)read the online
     documentation for abbrevs (`C-h i m XEmacs RET m Abbrevs RET'),
     and then come back and read this question/answer again.

   Newsflash: this restriction has been lifted, starting with XEmacs
20.3, which is currently in beta.  Hrvoje Niksic <hniksic@srce.hr> will
appreciate it if you download a beta, try out whether abbreviations work
like you expect them to, and let him know.


File: xemacs-faq.info,  Node: Q5.3.10,  Next: Q5.3.11,  Prev: Q5.3.9,  Up: Miscellaneous

How can I get those oh-so-neat X-Face lines?
============================================

   Firstly there is an ftp site which describes X-faces and has the
associated tools mentioned below, at
<URL:ftp://ftp.cs.indiana.edu:/pub/faces/>.

   Then the steps are

  1. Create 48x48x1 bitmap with your favorite tool

  2. Convert to "icon" format using one of xbm2ikon, pbmtoicon, etc.,
     and then compile the face.

  3.      cat file.xbm | xbm2ikon |compface > file.face

  4. Then be sure to quote things that are necessary for emacs strings:

          cat ./file.face | sed 's/\\/\\\\/g'  | sed 's/\"/\\\"/g' > ./file.face.quoted

  5. Then set up emacs to include the file as a mail header - there
     were a couple of suggestions here--either something like:

          (setq  mail-default-headers
            "X-Face:  <Ugly looking text string here>")

     Or, alternatively, as:

          (defun mail-insert-x-face ()
            (save-excursion
              (goto-char (point-min))
              (search-forward mail-header-separator)
              (beginning-of-line)
              (insert "X-Face:")
              (insert-file-contents "~/.face")))
          
          (add-hook 'mail-setup-hook 'mail-insert-x-face)

   However, 2 things might be wrong:

   Some versions of pbmtoicon produces some header lines that is not
expected by the version of compface that I grabbed. So I found I had to
include a `tail +3' in the pipeline like this:

     cat file.xbm | xbm2ikon | tail +3 |compface > file.face

   Some people have also found that if one uses the `(insert-file)'
method, one should NOT quote the face string using the sed script .

   It might also be helpful to use Stig's <stig@hackvan.com> script
(included in the compface distribution at XEmacs.org) to do the
conversion.  For convenience xbm2xface is available for anonymous FTP at
<URL:ftp://ftp.miranova.com/pub/xemacs/xbm2xface.pl>.

   Contributors for this item:

   Paul Emsley, Ricardo Marek, Amir J. Katz, Glen McCort, Heinz Uphoff,
Peter Arius, Paul Harrison, and Vegard Vesterheim


File: xemacs-faq.info,  Node: Q5.3.11,  Next: Q5.3.12,  Prev: Q5.3.10,  Up: Miscellaneous

How do I add new Info directories?
==================================

   You use something like:

     (setq Info-directory-list (cons
     			    (expand-file-name "~/info")
      			    Info-default-directory-list))

   David Masterson <davidm@prism.kla.com> writes:

     Emacs Info and XEmacs Info do many things differently.  If you're
     trying to support a number of versions of Emacs, here are some
     notes to remember:

       1. Emacs Info scans `Info-directory-list' from right-to-left
          while XEmacs Info reads it from left-to-right, so append to
          the *correct* end of the list.

       2. Use `Info-default-directory-list' to initialize
          `Info-directory-list' *if* it is available at startup, but not
          all Emacsen define it.

       3. Emacs Info looks for a standard `dir' file in each of the
          directories scanned from #1 and magically concatenates them
          together.

       4. XEmacs Info looks for a `localdir' file (which consists of
          just the menu entries from a `dir' file) in each of the
          directories scanned from #1 (except the first), does a simple
          concatenation of them, and magically attaches the resulting
          list to the end of the menu in the `dir' file in the first
          directory.

     Another alternative is to convert the documentation to HTML with
     texi2html and read it from a web browser like Lynx or W3.


File: xemacs-faq.info,  Node: Q5.3.12,  Prev: Q5.3.11,  Up: Miscellaneous

What do I need to change to make printing work?
===============================================

   For regular printing there are two variables that can be customized.

`lpr-command'
     This should be set to a command that takes standard input and sends
     it to a printer.  Something like:

          (setq lpr-command "lp")

`lpr-switches'
     This should be set to a list that contains whatever the print
     command requires to do its job.  Something like:

          (setq lpr-switches '("-depson"))

   For postscript printing there are three analogous variables to
customize.

`ps-lpr-command'
     This should be set to a command that takes postscript on standard
     input and directs it to a postscript printer.

`ps-lpr-switches'
     This should be set to a list of switches required for
     `ps-lpr-command' to do its job.

`ps-print-color-p'
     This boolean variable should be set `t' if printing will be done in
     color, otherwise it should be set to `nil'.

   NOTE: It is an undocumented limitation in XEmacs that postscript
printing (the `Pretty Print Buffer' menu item) *requires* a window
system environment.  It cannot be used outside of X11.


File: xemacs-faq.info,  Node: Current Events,  Prev: Miscellaneous,  Up: Top

What the Future Holds
*********************

   This is part 6 of the XEmacs Frequently Asked Questions list.  This
section will change monthly, and contains any interesting items that
have transpired over the previous month.  If you are reading this from
the XEmacs distribution, please see the version on the Web or archived
at the various FAQ FTP sites, as this file is surely out of date.

* Menu:

* Q6.0.1::      What is new in 20.2?
* Q6.0.2::      What is new in 20.3?
* Q6.0.3::      Procedural changes in XEmacs development.


File: xemacs-faq.info,  Node: Q6.0.1,  Next: Q6.0.2,  Prev: Current Events,  Up: Current Events

What is new in 20.2?
====================

   The biggest changes in 20.2 include integration of EFS (the next
generation of ange-ftp) and AUC Tex (the Emacs subsystem that includes a
major mode for editing Tex and LaTeX, and a lot of other stuff).  Many
bugs from 20.0 have been fixed for this release.  20.2 also contains a
new system for customizing XEmacs options, invoked via `M-x customize'.

   XEmacs 20.2 is the development release (20.0 was beta), and is no
longer considered unstable.


File: xemacs-faq.info,  Node: Q6.0.2,  Next: Q6.0.3,  Prev: Q6.0.1,  Up: Current Events

What is new in 20.3?
====================

   XEmacs 20.3 will be released in November 1997.  It will contain many
bugfixes, and a number of new features, including Autoconf 2 based
configuration, multiple TTY frames, further customizations, synches with
GNU Emacs 20, advanced Perl-like regexp features, and more.

   XEmacs 20.3 will be the first non-beta v20 release, and will be the
basis for all further development.


File: xemacs-faq.info,  Node: Q6.0.3,  Prev: Q6.0.2,  Up: Current Events

Procedural changes in XEmacs development.
=========================================

  1. Discussion about the development of XEmacs occurs on the
     xemacs-beta mailing list.  Subscriptions to this list will now be
     fully automated instead of being handled by hand.  Send a mail
     message to <xemacs-beta-request@xemacs.org> with a subject of
     subscribe to join the list.  Please note this is a developers
     mailing list for people who have an active interest in the
     development process.

     The discussion of NT XEmacs development is taking place on a
     separate mailing list.  Send mail to
     <xemacs-nt-request@xemacs.org> to subscribe.

  2. Due to the long development cycle in between releases, it has been
     decided that intermediate versions will be made available in
     source only form for the truly interested.

     XEmacs 19.16 was the last 19 release, basically consisting of
     19.15 plus the collected bugfixes.

  3. As of December 1996, Steve Baur <steve@altair.xemacs.org> has
     become the lead maintainer of XEmacs.


