\input texinfo    @c -*-texinfo-*-
@comment %**start of header
@setfilename speechd-el.info
@set VERSION 2.8
@settitle speechd-el @value{VERSION}
@syncodeindex fn cp
@syncodeindex ky cp
@syncodeindex vr cp
@comment %**end of header
@copying
This manual is for speechd-el, @value{VERSION}.

Copyright @copyright{} 2003, 2004, 2005, 2006, 2007, 2008, 2010 Brailcom, o.p.s.
Copyright @copyright{} 2012, 2013, 2016 Milan Zamazal

@quotation
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.2 or
any later version published by the Free Software Foundation; with no
Invariant Sections, with no Front-Cover Texts and no Back-Cover Texts.
A copy of the license is included in the section entitled ``GNU Free
Documentation License.''
@end quotation

You can also (at your option) distribute this manual under the GNU
General Public License:

@quotation
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 3 of the License, or (at your
option) any later version.

A copy of the license is included in the section entitled ``GNU
General Public License''.
@end quotation

@end copying

@dircategory Emacs
@direntry
* speechd-el: (speechd-el).	Emacs interface to Speech Dispatcher and BRLTTY.
@end direntry

@titlepage
@title speechd-el
@subtitle for version @value{VERSION}
@author Milan Zamazal
@author Brailcom, o.p.s.
@page
@vskip 0pt plus 1filll
@insertcopying
@end titlepage

@contents

@ifnottex
@node Top, Introduction, (dir), (dir)
@top speechd-el

@insertcopying
@end ifnottex

@menu
* Introduction::                What is speechd-el and this manual about?
* speechd-el User Manual::      Using Emacs speech output.
* speechd-el Elisp Library::    Using speechd-el in Elisp programs.
* Contact Information::         Bug reporting etc.

* Copying This Manual::         GNU Free Documentation License.
* Index::                       Concept, function, variable and key index.
@end menu

@c ****************************************************************************

@node Introduction, speechd-el User Manual, Top, Top
@chapter Introduction

speechd-el is an Emacs client to speech synthesizers, Braille displays
and other alternative output interfaces. It provides full speech and
Braille output environment for Emacs.

It is aimed primarily at visually impaired users who need non-visual
communication with Emacs, but it can be used by anybody who needs
sophisticated speech or other kind of alternative output from Emacs.
speechd-el can make Emacs a completely speech and BRLTTY enabled
application suitable for visually impaired users or, depending on its
configuration, it can only speak in certain situations or when asked,
to serve needs of any Emacs user.

Programming interfaces are available both to the user interface and
for communication with the output devices.

This manual describes the speech/Braille output user interface, how to
customize and extend the interface, and the Emacs Lisp libraries.
Some degree of familiarity with Speech Dispatcher or BRLTTY on the
user level is recommended, although not absolutely necessary.

@menu
* Design Goals::                
* Feature List::                
* Components::                  
@end menu

@node Design Goals, Feature List, Introduction, Introduction
@section Design Goals

speechd-el was designed considering our experience with other free
accessibility technologies.  We sometimes meet problems such as lack
of maintenance power, duplicated efforts, making technology specific
solutions instead of generally useful tools, important bugs.  As other
@uref{http://www.freebsoft.org/projects,Free(b)soft projects}
speechd-el attempts to fill in an empty space in the accessibility
area, in a way oriented towards future.  speechd-el tries to offer
technology that is useful, simple, supporting general accessibility
architecture models and that effectively utilizes the limited
accessibility development resources.

The particular speechd-el design goals are:

@itemize @bullet
@item
Providing advanced accessible user environment that works out of the
box and utilizes standard Emacs features wherever possible.  Emacs
accessibility should work as much as possible on the general level
without necessity to implement direct support for particular Emacs
packages.  speechd-el should also preferrably use standard Emacs
features if possible instead of implementing its own solutions.

@item
Implementing just the necessary functionality, without duplicating
features presented in other components such as Speech Dispatcher,
speech synthesizers or Braille APIs.  Emacs accessibility solutions
should share features, configuration, code, etc. with other
applications to the highest possible extent in order to make life of
both users and developers easier.

@item
Simple and clean source code that requires only minimum maintenance
and allows future extensions.

@item
As little modifications to standard Emacs environment as possible,
with the possibility to make additional customizations if needed,
either shared or private.  Emacs should work the same way whether it
speaks or not.  Of course optional customizations can be made and the
generally useful ones should be included as optional parts of the
distribution.

@item
Ability to work well in a multilingual environment.

@item
Completely Free Software architecture, without requiring any
proprietary component.
@end itemize

@node Feature List, Components, Design Goals, Introduction
@section Feature List

Major speechd-el features are:
@cindex features

@itemize @bullet
@item
Speech output.

@item
Braille display output and input, mostly identical to the speech
output.

@item
Both automated and explicit reading.  You can let Emacs read
everything and/or you can ask it to read some parts of the text (such
as current line, current buffer, last message, etc.).

@item
Message priorities ensuring you don't miss important messages while
you needn't listen to or view unimportant messages.

@item
``Intelligent'' and customizable selection of text to be read based on
lines, text properties, buffer contents changes and other criteria.

@item
Support for changing speech parameters (such as language, voice, rate,
pitch, volume, speech synthesizer).  Different speech parameters can
be used in different buffers, major modes, faces, etc.

@item
Support for events (such as sound icons).

@item
Emacs status changes reporting (such as mode, keyboard, process
changes, etc.).

@item
Multilingual environment support.  speechd-el works well with
languages other than English and offers support for current language
selection based on the kind of texts, selected keyboard, etc.

@item
Reasonable immediate speech and Braille output in most Emacs packages.

@item
No significant changes of the standard Emacs behavior.

@item
Speech and Braille output can be enabled/disabled independently to
each other and they can be enabled/disabled for the whole Emacs
session or just for particular buffers.

@item
Speech synthesizer independence, you can use all speech synthesizers
supported by Speech Dispatcher (such as Festival, Flite, eSpeak, Epos,
Dectalk, IBM TTS, Cicero, etc.) and you can use multiple speech
synthesizers inside a single Emacs session.

@item
Braille displays are handled through BRLTTY drivers and APIs.

@item
Programming libraries for those who want to extend speechd-el
facilities or who just want to talk to speech synthesizers, Braille
display or other output/input devices.

@item
Special features for speechd-el developers such as silence in
debugger, debugging variables, possibility to disable speechd-el
hooks, etc.

@item
Small code size.
@end itemize

See @uref{http://www.freebsoft.org/speechd-el,speechd-el web page} if
you are interested in comparison with Emacspeak.

@node Components,  , Feature List, Introduction
@section Components

speechd-el design is strictly modular.  It contains several components
layered each on top of other.  Lower layer functions can be used
independently of higher level features.

@cindex SSIP
@cindex BrlAPI
The lowest level components are access libraries to output devices,
especially to SSIP (the Speech Dispatcher TCP communication protocol
for speech output) and BrlAPI (interface to BRLTTY drivers for
communication with Braille displays).  They can be used to talk to the
output devices directly from Elisp programs.

The next level implements common access to all the devices.  Instead
of talking to each device independently one can use this layer to
output device independent messages that are processed and sent to the
output devices as defined in the user configuration.  This is the
preferred way of communication with the output devices.

On the highest level there is the user interface frontend that makes
Emacs read texts and events automatically, defines the corresponding
minor modes, key bindings and most of the interactive commands.

There are some other auxiliary components, look into speechd-el source
code if interested.

@c ****************************************************************************

@node speechd-el User Manual, speechd-el Elisp Library, Introduction, Top
@chapter speechd-el User Manual

speechd-el allows you to use Emacs without looking at screen, with
speech or Braille output only.  The main usage area is by blind and
visually impaired people, but generally you can use at least the
speech output for many purposes, according to your wishes and needs.

You can download the latest released version of speechd-el from
@url{http://www.freebsoft.org/pub/projects/speechd-el/}.

speechd-el uses Speech Dispatcher for the speech output, so working
Speech Dispatcher installation is necessary to produce any speech
output.  Please look at @url{http://www.freebsoft.org/speechd} for
more information about Speech Dispatcher.

@cindex BRLTTY
For the Braille output BRLTTY is used through its BrlAPI interface.
To make the Braille output work, BRLTTY must be running and properly
configured.  Please look at @url{http://www.mielke.cc/brltty/} for
more information about BRLTTY.

@menu
* Installation::                Installing speechd-el.
* Starting Alternative Output:: Making it speak etc.
* Commands::                    Usage.
* Customization::               Basic customization.
* Advanced Customization::      Writing your own command feedbacks.
* Problems::                    Strange behavior.
* Tips::                        Useful Emacs tips.
* Bug Reporting::               speechd-el and Speech Dispatcher bugs.
@end menu

@node Installation, Starting Alternative Output, speechd-el User Manual, speechd-el User Manual
@section Installation

speechd-el installation consists of the following steps:

@enumerate
@item
If you use Emacs older than 23.2 then install the @samp{eieio} Elisp
library, available from @url{http://cedet.sourceforge.net/eieio.shtml}
or perhaps your favorite operating system distribution.

@item
Copy the speechd-el @file{*.el} files contained in the distribution
package somewhere to your Emacs load path.

@item
If you like, byte compile the @file{*.el} files.  Byte compilation is
recommended, because it speeds up speechd-el significantly.  You can
byte compile the @file{*.el} files using the command

@example
make compile
@end example

Then install the compiled files to an Emacs load path location as
well.

@item
Install the @file{speechd-log-extractor} somewhere to your shell PATH,
e.g. @file{/usr/local/bin/}.  Installing this script is optional, it
is used only for bug reporting.

@item
Add the following line to your @file{~/.emacs}:

@lisp
(autoload 'speechd-speak "speechd-speak" nil t)
@end lisp
@end enumerate

@cindex Speech Dispatcher
To receive speech output, Speech Dispatcher must be installed and
running.  Speech Dispatcher version 0.5 or higher is recommended.

@cindex BRLTTY
To receive Braille output, BRLTTY must be installed and running.
BRLTTY version 3.7 or higher is required.

@node Starting Alternative Output, Commands, Installation, speechd-el User Manual
@section Starting Speech and Braille Output

After installation of the @file{*.el} files and restarting Emacs, you
can set up speechd-speak using the @kbd{M-x speechd-speak} command.
If you want to happen it automatically each time Emacs is started, put
the following line to your @file{~/.emacs} after the autoload line:

@lisp
(speechd-speak)
@end lisp

@table @kbd
@item M-x speechd-speak
@findex speechd-speak
@kindex C-e C-s
Set up Emacs for alternative output and start speaking or
communicating with the Braille display.

Please don't forget Speech Dispatcher must be running in order to get
any speech output and BRLTTY must be running in order to get Braille
output!

After the initial setup, the command can be used again to restart the
speech or Braille output when needed.  Especially, you must run it
again if Speech Dispatcher or BRLTTY gets restarted.

After the first invocation, the command is available under the
@kbd{C-e C-s} key.
@end table

@cindex minor modes
Once the setup is done, enabling and disabling the alternative output
is controlled by the speechd-speak and global-speechd-speak minor
modes.  Usually the mode commands are not used directly, you use the
@code{speechd-speak-toggle-speaking} command (@pxref{Control
Commands}), but if you need them, they are available.

@table @kbd
@item M-x speechd-speak-mode
@findex speechd-speak-mode
Enable or disable speaking and Braille output in the current buffer.
With no argument, this command toggles the mode.  Non-null prefix
argument turns on the mode.  Null prefix argument turns off the mode.

@item M-x global-speechd-speak-mode
@findex global-speechd-speak-mode
Enable or disable alternative output globally.  With no argument, this
command toggles the mode.  With prefix argument, turn alternative
output on if and only if the argument is positive.
@end table

@node Commands, Customization, Starting Alternative Output, speechd-el User Manual
@section Commands

The basic speechd-el commands are all accessible through a common
special prefix key, which is @kbd{C-e} by default (you can change it,
@pxref{Customization}).  If this prefix conflicts with a global Emacs
command, the original command is available by double pressing the
prefix key.  For instance, with the default prefix, the
@code{end-of-line} command, normally available under the @kbd{C-e}
key, can be invoked as @kbd{C-e C-e}.

In the following subsections we use the term @emph{reading} to
indicate any kind of output enabled in speechd-el (such as speaking or
Braille output).

@menu
* Reading Commands::            Reading pieces of text.
* Informatory Commands::        Information about buffer, modes, etc.
* Control Commands::            Stopping, setting speech rate, etc.
* Parameter Setting Commands::  Modifying speech output.
* Spelling::                    How to spell a piece of text.
* Other Commands::              Auxiliary commands.
@end menu

@node Reading Commands, Informatory Commands, Commands, Commands
@subsection Reading Commands

@table @kbd
@item C-e l
@kindex C-e l
@findex speechd-speak-read-line
Read current line (@code{speechd-speak-read-line}).  With the prefix
argument, read the line only from the current cursor position to the
end of line.

@item C-e b
@kindex C-e b
@findex speechd-speak-read-buffer
Read current buffer (@code{speechd-speak-read-buffer}).

@item C-e >
@kindex C-e >
@findex speechd-speak-read-rest-of-buffer
Read current buffer from the cursor to the buffer end
(@code{speechd-speak-read-rest-of-buffer}).

@item C-e o
@kindex C-e o
@findex speechd-speak-read-other-window
Read buffer of the other window, if any is present
(@code{speechd-speak-read-other-window}).

@item C-e r
@kindex C-e r
@findex speechd-speak-read-region
Read current region (@code{speechd-speak-read-region}).

@item C-e C-r
@kindex C-e C-r
@findex speechd-speak-read-rectangle
Read text in the rectangle-region (@code{speechd-speak-read-rectangle}).

@item C-e w
@kindex C-e w
@findex speechd-speak-read-word
Read the next word after cursor (@code{speechd-speak-read-word}).

@item C-e .
@kindex C-e .
@findex speechd-speak-read-sentence
Read current sentence (@code{speechd-speak-read-sentence}).

@item C-e @{
@kindex C-e @{
@findex speechd-speak-read-paragraph
Read the next paragraph after cursor (@code{speechd-speak-read-paragraph}).

@item C-e [
@kindex C-e [
@findex speechd-speak-read-page
Read the next page after cursor (@code{speechd-speak-read-page}).

@item C-e '
@kindex C-e '
@findex speechd-speak-read-sexp
Read the next symbolic expression after cursor
(@code{speechd-speak-read-sexp}).

@item C-e c
@kindex C-e c
@findex speechd-speak-read-char
Read the character at the cursor position (@code{speechd-speak-read-char}).

@item C-e C-n
@kindex C-e C-n
@findex speechd-speak-read-next-line
Read the next line (@code{speechd-speak-read-next-line}).

@item C-e C-p
@kindex C-e C-p
@findex speechd-speak-read-previous-line
Read the previous line (@code{speechd-speak-read-previous-line}).

@item C-e m
@kindex C-e m
@findex speechd-speak-last-message
Read last seen Emacs message (@code{speechd-speak-last-message}).

@item C-e RET
@cindex mode line
@kindex C-e RET
@findex speechd-speak-read-mode-line
Read the mode line (@code{speechd-speak-read-mode-line}).  Note: This
command works only in Emacs@tie{}22 or higher.

@item C-e i
@kindex C-e i
@findex speechd-speak-last-insertions
Read last output buffer insertions
(@code{speechd-speak-last-insertions}).  That is the text read in
auto-reading buffers, see @xref{Auto-Reading Buffers}.
@end table

@cindex character reading prompts
@cindex read-char
A few Emacs commands get you stuck in a character reading prompt, a
typical example is @code{ispell-word}.  If you miss what was read
before you are prompted for action, you can use the following
keystrokes at the prompt to repeat the output texts:

@table @kbd
@item C-e
@findex speechd-speak-last-message
The same as the @kbd{C-e m} command above
(@code{speechd-speak-last-message}).

@item C-a
@findex speechd-speak-last-insertions
The same as the @kbd{C-e i} command above
(@code{speechd-speak-last-insertions}).
@end table

If you don't like such character reading prompt behavior, you can
disable it using the following variable:

@vtable @code
@item speechd-speak-allow-prompt-commands
If non-@code{nil}, allow the speechd-speak commands mentioned above in
read-char prompts.
@end vtable

@node Informatory Commands, Control Commands, Reading Commands, Commands
@subsection Informatory Commands

@table @kbd
@item C-e C-i b
@findex speechd-speak-buffer-info
@cindex buffer
Read information about current buffer
(@code{speechd-speak-buffer-info}).

@item C-e C-i f
@findex speechd-speak-frame-info
@cindex frame
Read information about current frame (@code{speechd-speak-frame-info}).

@item C-e C-i h
@findex speechd-speak-header-line-info
@cindex header line
Read contents of the header line
(@code{speechd-speak-header-line-info}).  Note: This command works
only in Emacs@tie{}22 or higher.

@item C-e C-i m
@findex speechd-speak-mode-info
@cindex modes
Read information about current major and minor modes
(@code{speechd-speak-mode-info}).

@item C-e C-i c
@findex speechd-speak-coding-info
@cindex coding systems
Read information about current coding systems
(@code{speechd-speak-coding-info}).

@item C-e C-i i
@findex speechd-speak-input-method-info
@cindex input method
Read information about current input method
(@code{speechd-speak-input-method-info}).

@item C-e C-i p
@findex speechd-speak-process-info
@cindex process
Read status of the process associated with the current buffer
(@code{speechd-speak-process-info}).
@end table

@node Control Commands, Parameter Setting Commands, Informatory Commands, Commands
@subsection Control Commands

@table @kbd
@item C-e q
@kindex C-e q
@findex speechd-speak-toggle-speaking
@cindex shutting up
Toggle reading globally (@code{speechd-speak-toggle-speaking}).  With
a prefix argument, toggle it in the current buffer only.

@item C-e s
@kindex C-e s
@findex speechd-stop
@cindex stop
Stop reading current message (@code{speechd-stop}).  Other queued
messages will still be read.  If the prefix argument is given, stop
reading the current message of any client, not just of the current
connection.

@item C-e x
@kindex C-e x
@findex speechd-cancel
@cindex stop
Stop reading all the queued messages of the current connection and of
the connections listed in @var{speechd-cancelable-connections}.  If
the universal prefix argument is given, stop reading all the messages
of all connections.  If a numeric prefix argument is given, stop all
the messages of the current Emacs session.

@item C-e p
@kindex C-e p
@findex speechd-pause
@cindex pause
Pause reading --- just be quiet for now and postpone current reading
until the resume command is invoked (@code{speechd-pause}).  If the
prefix argument is given, pause reading of all clients.

@item C-e SPC
@kindex C-e SPC
@findex speechd-resume
@cindex resume
Resume paused reading (@code{speechd-resume}).  If the
prefix argument is given, resume reading of all clients.

@item C-e 1
@itemx C-e 2
@itemx C-e 3
@itemx C-e 4
@itemx C-e 5
@itemx C-e 6
@itemx C-e 7
@itemx C-e 8
@itemx C-e 9
@kindex C-e 1
@kindex C-e 2
@kindex C-e 3
@kindex C-e 4
@kindex C-e 5
@kindex C-e 6
@kindex C-e 7
@kindex C-e 8
@kindex C-e 9
@findex speechd-speak-key-set-predefined-rate
@cindex rate
Set one of the predefined speech rates
(@code{speechd-speak-key-set-predefined-rate}).  @kbd{C-e 1} sets the
slowest rate, @kbd{C-e 5} sets the medium rate, and @kbd{C-e 9} sets
the fastest rate.
@end table

@node Parameter Setting Commands, Spelling, Control Commands, Commands
@subsection Parameter Setting Commands
@cindex parameters

These commands set various properties of the speech output.  They all
apply on the current Speech Dispatcher connection (for more
information about Speech Dispatcher connections, @pxref{Connection
Voices}), unless there are invoked with a prefix argument.  With a
numeric prefix argument they apply on all speechd-el connections, with
a universal prefix argument they apply on all Speech Dispatcher
connections.

Commands affecting basic parameters of the text-to-speech process:

@table @kbd
@item C-e d l
@kindex C-e d l
@findex speechd-speak-set-language
@cindex language
Set default language of the connection.  Specify it as an RFC 1766
language code (e.g. @code{en}, @code{cs}, etc.).

@item C-e d .
@kindex C-e d .
@findex speechd-set-punctuation-mode
@cindex punctuation mode
Specify how to handle punctuation, whether to read it or ignore it.
@code{all} mode reads all punctuation characters, @code{none} mode
skips them all quietly, and @code{some} mode reads a selected subset
of punctuation characters specified in the Speech Dispatcher
configuration.

@item C-e d c
@kindex C-e d c
@findex speechd-set-capital-character-mode
@cindex capital character mode
Set capital letter indication mode.  @code{icon} means signal them
with a sound icon, @code{spell} means spell them using a special
spelling table, and @code{none} means no indication.
@end table

Commands affecting speech output properties:

@table @kbd
@item C-e d v
@kindex C-e d v
@findex speechd-set-voice
@cindex voice
Set default voice to be used by the synthesizer
(@code{speechd-set-voice}).  You may select one from the voice set
offered by your Speech Dispatcher installation.

@item C-e d C-v
@kindex C-e d C-v
@findex speechd-set-synthesizer-voice
@cindex voice
Set default voice to be used by the synthesizer directly by its
synthesizer dependent name (@code{speechd-set-synthesizer-voice}).
You may select one from the voice set offered by the currently
selected Speech Dispatcher output module.  This works only with Speech
Dispatcher 0.6.3 or higher and not all Speech Dispatcher output
modules support this function.

@item C-e d r
@kindex C-e d r
@findex speechd-set-rate
@cindex rate
Set exact speech rate, ranging from -100 (slowest) to 100 (fastest)
(@code{speechd-set-rate}).  Most often you will probably want to
use the @code{speechd-speak-key-set-predefined-rate} command bound to
@kbd{C-e @var{number}} instead, see @ref{Control Commands}.

@item C-e d p
@kindex C-e d p
@findex speechd-set-pitch
@cindex pitch
Set voice pitch, ranging from -100 (lowest) to 100 (highest)
(@code{speechd-set-pitch}).

@item C-e d V
@kindex C-e d V
@findex speechd-set-volume
@cindex volume
Set voice volume, ranging from -100 (lowest) to 100 (highest)
(@code{speechd-set-volume}).
@end table

Commands affecting the speech synthesizer:

@table @kbd
@item C-e d o
@kindex C-e d o
@findex speechd-set-output-module
@cindex output module
Switch Speech Dispatcher to the given output module
(@code{speechd-set-output-module}).  Give the module name when
you are prompted for the argument.
@end table

@node Spelling, Other Commands, Parameter Setting Commands, Commands
@subsection Spelling
@cindex spelling

@cindex speechd-speak-spell-mode
There are two ways to use spelling in speechd-el.  The first one is
the @code{speechd-speak-spell-mode}, which is a minor mode that you
can enable for a buffer.  The mode is useful if you want to spell more
of the buffer contents.

The second spelling method is using the following command:

@table @kbd
@item C-e C-l
@kindex C-e C-l
@findex speechd-speak-spell
Cause the following command to spell the text it reads
(@code{speechd-speak-spell}).  For instance, if you want to spell the
word after the cursor, you can type @kbd{C-e C-l C-e w}.
@end table
 
@node Other Commands,  , Spelling, Commands
@subsection Other Commands

@kindex C-x C-c
In case Emacs gets completely crazy and refuses to run commands
including @kbd{C-x C-c} because of a bug in speechd-el or in an
alternative output related custom definition, you can try to invoke
the following command as the last resort:

@table @kbd
@item C-e C-x
@kindex C-e C-x
@findex speechd-unspeak
@cindex recovery
Try to disable all modes, hooks and wrappers installed by
@code{speechd-speak} (@code{speechd-unspeak}).
@end table

The following commands are rarely used, mostly for diagnosing
purposes:

@table @kbd
@item C-e z
@kindex C-e z
@findex speechd-repeat
Repeat the last output text
(@code{speechd-repeat}).

@item M-x speechd-say-text
@findex speechd-say-text
Prompt for a text and read it.
@end table

@node Customization, Advanced Customization, Commands, speechd-el User Manual
@section Customization

All the customization options described below are accessible in the
customization group @samp{speechd-el} and its subgroups.

@menu
* Driver Selection::            Choosing output devices.
* Connection Setup::            Where to connect to.
* Default Priorities::          Priorities of various kinds of messages.
* Basic Speaking::              Simple options.
* Auto-Reading Buffers::        Making certain buffers speak automatically.
* Reading State::               Speaking Emacs state changes.
* Signalling::                  Signalling empty lines, etc.
* Text Properties::             Handling faces and special pieces of text.
* Languages::                   Using multiple languages.
* Voices::                      Defining different voices.
* Connection Voices::           Setting connection parameters.
* Multiple Connections::        Different parameters for some modes & buffers.
* Keys::                        Customizing command keys.
* Braille Display Keys::        Binding actions to Braille display keys.
* Modes::                       Minor mode hooks.
* Debugging::                   Make debugger quiet.
@end menu

@node Driver Selection, Connection Setup, Customization, Customization
@subsection Selecting Drivers

By default speechd-el speaks to @code{ssip} and @code{brltty}
drivers.  You can change the set of active drivers by customizing the
following variable:

@vtable @code
@item speechd-out-active-drivers
List of names of active output drivers.
@end vtable

If a driver that does not work is present in the variable (e.g. the
list contains the @code{brltty} symbol while BRLTTY is not actually
running), you receive an error message.  To prevent the error message,
remove the driver from this variable.

When you want to enable or disable some driver temporarily, you can
use the following commands:

@ftable @kbd
@item M-x speechd-out-enable-driver
@findex speechd-out-enable-driver
Enable the given output driver.

@item M-x speechd-out-disable-driver
@findex speechd-out-disable-driver
Disable the given output driver.
@end ftable

@node Connection Setup, Default Priorities, Driver Selection, Customization
@subsection Speech Dispatcher Connection Configuration

Connection configuration variables allow you connect to Speech
Dispatcher or BRLTTY running on a remote host or a non-default port
and to specify other TCP connection parameters.

Speech Dispatcher connection options:

@vtable @code
@item speechd-connection-method
Connection method to Speech Dispatcher.  Possible values are symbols
@code{unix-socket} for Unix domain sockets and @code{inet-socket} for
Internet sockets on a given host and port.

@item speechd-host
@cindex host
Name of the host running Speech Dispatcher to connect to, given as a
string.  Default is either the contents of the shell variable
@code{SPEECHD_HOST} variable if set, or @code{"localhost"}.  Value of
this variable matters only when Internet sockets are used for
communication with Speech Dispatcher.

@item speechd-port
@cindex port
Port number to connect to.  Default is either the contents of the
shell variable @code{SPEECHD_PORT} if set, or the default Speech
Dispatcher port.  Value of this variable matters only when Internet
sockets are used for communication with Speech Dispatcher.

@item speechd-autospawn
If non-@code{nil}, Emacs will attempt to automatically start Speech
Dispatcher.  This means that if speechd-el gets a speech request and
the Speech Dispatcher server is not running already, speechd-el will
launch it.

@item speechd-timeout
@cindex timeout
Maximum number of seconds to wait for a Speech Dispatcher answer.  If
it is exceeded, speechd-el closes the connection.  Normally, Speech
Dispatcher should answer protocol commands immediately, but if you
talk to a Speech Dispatcher in a strange way through a lagging
network, you may want to increase the limit.

@item speechd-spdsend
@cindex spdsend
If non-@code{nil}, it is a string naming the @emph{spdsend} binary
(normally @code{"spdsend"}) to use for communication with Speech
Dispatcher.  If @code{nil} or if you use Emacs@tie{}22 or higher,
spdsend is not used.

Usually you shouldn't care about this variable.
@end vtable

BRLTTY connection options:

@vtable @code
@item brltty-default-host
Name of the host running BRLTTY to connect to, given as a string.
Default is @code{"localhost"}.

@item brltty-default-port
Port number to connect to.  It can be either a single number or a list
of numbers; in the latter case the given port numbers are attempted in
the order they are given until Emacs connects to something.  Default
is the list of the standard BrlAPI ports.

@item brltty-authentication-file
File containing the BrlAPI authentication key.  It is important to set
the variable properly, otherwise the connection to BRLTTY gets
rejected.  Default is @code{"/etc/brlapi.key"}.

@item brltty-coding
Coding in which texts should be sent to BRLTTY.  Default is
@code{iso-8859-1}; if you use non-Western language, you may need to
change it to display its characters correctly on the Braille display.

@item brltty-tty
Number of the Linux console on which speechd-el runs.  If this value
is not set correctly, speechd-el may not interact well with other
applications communicating with BRLTTY.  speechd-el tries to find the
correct value itself, if this doesn't work, set this variable properly
or set the @code{CONTROLVT} environment variable.

@item brltty-timeout
Maximum number of seconds to wait for a BRLTTY answer.  If it is
exceeded, speechd-el closes the connection.  Normally, BRLTTY should
answer protocol commands immediately, but if you talk to BrlAPI in a
strange way through a lagging network, you may want to increase the
limit.
@end vtable

@node Default Priorities, Basic Speaking, Connection Setup, Customization
@subsection Default Priorities
@cindex priorities

If a speechd-el function sends a message to the output device without
an explicitly specified priority, the priorities defined by the
following variables are used.  By changing the values, you can achieve
interesting effects.  For instance, changing the value of
@code{speechd-default-key-priority} from @code{notification} to
@code{message} makes all typed characters to be echoed and makes them
to interrupt common text reading.

The valid values of all the variables here are: @code{important},
@code{message}, @code{text}, @code{notification}, @code{progress}.
They correspond to Speech Dispatcher priorities, see the Speech
Dispatcher manual for more details.

@vtable @code
@item speechd-default-text-priority
Default priority of most text messages.

@item speechd-default-sound-priority
Default priority of sound icons.

@item speechd-default-char-priority
Default priority of spelled characters.

@item speechd-default-key-priority
Default priority of typed keys.
@end vtable

@node Basic Speaking, Auto-Reading Buffers, Default Priorities, Customization
@subsection Basic Customization of Speaking

@vtable @code
@item speechd-speak-echo
@cindex echoing
Symbol determining how to read typed characters.  It can have one of
the following values:

@table @code
@item character
Read characters when they are typed.
@item word
Read only whole words once they are written.
@item nil
Don't echo anything on typing.
@end table

@item speechd-speak-deleted-char
@cindex deletions
Defines which character to speak when deleting a character.  If
non-@code{nil}, speak the deleted character, otherwise speak the
adjacent character.

@item speechd-speak-buffer-name
@cindex buffer names
When you switch to another buffer and this variable is non-@code{nil},
read the new buffer name.  If the variable value is the symbol
@code{text}, read the text from the cursor position to the end of
line in the new buffer as well.  If the variable is @code{nil}, read
the text without speaking the buffer name.

@item speechd-speak-whole-line
@cindex line reading
If non-@code{nil}, read whole line on movement by default.  Otherwise
read from the point to the end of line on movement by default.

@item speechd-speak-on-minibuffer-exit
@cindex minibuffer
When this variable is non-@code{nil}, speechd-el reads the text around
cursor after exiting from minibuffer or its recursive level if there
is nothing else to read.

@item speechd-speak-read-command-keys
@cindex command keys
@cindex keys
This variable defines in which situations command keys should be read
when their command is performed.  If @code{t}, the command keys are
always read.  If @code{nil}, they are never read.  If list, it may
contain one or more of the following symbols describing the situations
in which the keys should be read:

@table @code
@item movement
Read the command keys if the cursor has moved, no buffer modification
happened.

@item modification
Buffer was modified, the cursor hasn't moved.

@item movement-modification
Buffer was modified and the cursor was moved.
@end table

If the variable value is @code{t}, the command keys are read before
the command is performed.  Otherwise, their reading is delayed after
the command is executed, since the buffer changes and cursor movement
must be detected first.

@item speechd-speak-ignore-command-keys
@cindex command keys
@cindex keys
List of commands that should never echo their command keys.

@item speechd-speak-read-command-name
@cindex command name
If non-@code{nil}, read the command name instead of the command keys
in the situations defined by the variable
@code{speechd-speak-read-command-keys}.

@item speechd-speak-message-time-interval
@cindex messages
@cindex repeating
Minimum time in seconds, after which the same message may be repeated.
If the message is the same as the last one, it is not spoken unless the number
of seconds defined here has passed from the last spoken message.
@end vtable

@node Auto-Reading Buffers, Reading State, Basic Speaking, Customization
@subsection Auto-Reading Buffers
@cindex buffers
@cindex inserted text

It sometimes useful to start reading some buffers without user's
explicit request.  For instance, if a help command is invoked, the
user usually wants to read the help text immediately.  The following
variables contain lists of names of the buffers that may be read
automatically if they get changed by the last command and are visible
in some window of the current frame.

@vtable @code
@item speechd-speak-auto-speak-buffers
Content of these buffers is read after the command on the above
conditions if nothing else (e.g. text around a new cursor position) is
to be read.

@item speechd-speak-force-auto-speak-buffers
Like @code{speechd-speak-auto-speak-buffers} except that the buffer
content is read forcibly, even when something else could be read.
@end vtable

The following variables define how to handle texts inserted during
performing user commands.  Only newly inserted text is read, the
options don't affect processing of deleted text.  Also, the options
don't affect insertions within commands processed in a special way by
speechd-el or user definitions, like @code{self-insert-command}.

@vtable @code
@item speechd-speak-buffer-insertions
Defines whether insertions in the current buffer should be read
automatically.  The value may be one of the following symbols:

@table @code
@item nil
Don't read the inserted texts.

@item t
Read all the inserted texts.

@item one-line
Read only the first lines of inserted texts.

@item whole-buffer
Read whole buffer if it was modified in any way.
@end table

@item speechd-speak-insertions-in-buffers
List of names of buffers, in which insertions are automatically
read, whether the buffer is current or not and regardless the
@code{speechd-speak-buffer-insertions} variable.

@item speechd-speak-priority-insertions-in-buffers
List of names of buffers, in which insertions are automatically read
immediately as they appear, not only after a command is evaluated as
with @code{speechd-speak-insertions-in-buffers}.  This is typically
useful in comint buffers.

@item speechd-speak-align-buffer-insertions
If non-@code{nil}, the insertion text to be read is extended to the
beginning of the first word affected by the insertion.  This is
particularly useful in completion functions.
@end vtable

If the last command modified the current buffer and moved its cursor
to a completely different position, the new cursor position is not
indicated in the alternative output.  You can change it through the
following variable:

@vtable @code
@item speechd-speak-movement-on-insertions
If @code{t}, read the text around new cursor position even when the
current buffer was modified.  If @code{read-only}, read it only in
read-only buffers.  If @code{nil}, don't read it.
@end vtable

@node Reading State, Signalling, Auto-Reading Buffers, Customization
@subsection Reading State Changes

speechd-el can read information about current Emacs state, like
current buffer name, major and minor modes or other buffer attributes,
see @xref{Informatory Commands}.  Changes in the Emacs state
information can be reported automatically, according to the user
configuration:

@vtable @code
@item speechd-speak-state-changes
List of identifiers of the Emacs state changes to be automatically
reported.  The following symbols are recognized as state change
identifiers:

@table @code
@item buffer-name
@item buffer-identification
(only in Emacs@tie{}22 or higher)
@item buffer-modified
@item buffer-read-only
@item frame-name
@item frame-identification
(only in Emacs@tie{}22 or higher)
@item header-line
(only in Emacs@tie{}22 or higher)
@item major-mode
@item minor-modes
@item buffer-file-coding
@item terminal-coding
@item input-method
@item process
@end table

@item speechd-speak-display-modes
List of minor modes to be read by their display string rather than
name.  To use the display form of a mode identification may be useful
in cases when the display form is more concise than the mode name or
when the display form changes without actual change of the mode.
@end vtable

@node Signalling, Text Properties, Reading State, Customization
@subsection Signalling

@cindex icons
Certain situations may be signalled by icons.  @dfn{Icon} is typically
a short sound or a special indication on a Braille
display@footnote{Icons are not yet implemented this way in the Braille
library, plain texts are displayed instead.} signalling some event
(such as displaying a message, entering prompt, or reaching an empty
line).  The following variable enables or disables the predefined
indications.  To learn how to define your own indications,
@xref{Advanced Customization}.

@vtable @code
@item speechd-speak-signal-events
List of symbols, containing names of events to signal with an icon.
The following event names are supported:

@table @code
@item start
Start or restart of speechd-el.

@item empty
@cindex empty text
Empty text in various situations.

@item beginning-of-line
@cindex line
@cindex beginning of line
Reaching beginning of line after the
@code{forward-char} and @code{backward-char} commands.

@item end-of-line
@cindex end of line
Reaching end of line after the
@code{forward-char} and @code{backward-char} commands.

@item minibuffer
Entering minibuffer.

@item message
Messages in echo area follow.
@end table
@end vtable

@node Text Properties, Languages, Signalling, Customization
@subsection Text Properties
@cindex text properties
@cindex faces
@cindex cursor
@cindex movement

By default, after a movement command speechd-el reads the current
line.  But if the cursor position is surrounded by a text having text
properties (typically faces, but any text properties count),
speechd-el may read just the piece of the text around the cursor
having uniform properties.

Also, if font lock mode is enabled, faces may be mapped to different
voices.

@vtable @code
@item speechd-speak-by-properties-on-movement
Method of selection of the piece of text to be read on movement.
The variable may take one of the following values.

@table @asis
@item @code{nil}
Text properties are not considered at all.

@item @code{t}
All text properties are considered.

@item list of faces
Only the named faces are considered.
@end table

@item speechd-speak-by-properties-always
List of commands that always consider text properties, even when the
@code{speechd-speak-by-properties-on-movement} variable is @code{nil}.

@item speechd-speak-by-properties-never
List of commands that never consider text properties, even when the
@code{speechd-speak-by-properties-on-movement} variable is
non-@code{nil}.

@item speechd-speak-faces
This variable allows you to invoke actions when the cursor ends up on
a certain face after a user command is performed.  The variable value
is an alist with elements of the form @code{(@var{face}
. @var{action})}.

If a movement command leaves the cursor on a @var{face} and there is
no explicit reading bound to the command, @var{action} is invoked.
If @var{action} is a string, that string is read.  If @var{action}
is a function, it is invoked, with no arguments.

@item speechd-face-voices
Mapping of faces to voices.  The variable value is an alist with
elements of the form @code{(@var{face} . @var{voice})} where
@var{face} is a face and @var{voice} is a voice identifier defined in
@code{speechd-voices}, see @ref{Voices}.  Each face is spoken in the
corresponding voice.  If there's no item for a given face in this
variable, the face is spoken in the current voice.

Note that the mapping takes the effect only if font lock mode is
enabled.
@end vtable

@node Languages, Voices, Text Properties, Customization
@subsection Using multiple languages
@cindex languages

You can use speechd-el with multiple languages.  However, the process
can't be easily automated, since ordinary text does not contain any
information about its language.  So if you want to use speechd-el with
the output being spoken in multiple languages, you must provide
speechd-el some hints.

The language settings described below currently apply only to the
spoken output, to select the proper voice.  They don't affect the
Braille output; but you may want to set language coding for Braille,
@xref{Connection Setup}.

@vindex speechd-language
@cindex RFC 1766
The basic means for providing language information to speechd-el is
the variable @code{speechd-language}.  Each time speechd-el is about
to speak a piece of text, it checks the variable for the language code
and if it is non-@code{nil}, it speaks the text in the corresponding
language.  The non-@code{nil} value must be a string of the RFC 1766
language code (e.g. @code{en}, @code{cs}, etc.).

Most often you will probably want to set the variable in a particular
file, see @ref{File Variables,,,emacs,GNU Emacs Manual}, or as a
buffer local variable, see @ref{Locals,,,emacs,GNU Emacs
Manual}, in mode hooks, see @ref{Hooks,,,emacs,GNU Emacs Manual}.

@findex speechd-language
@cindex @code{language} text property
If a piece of the text has the @code{language} property containing the
RFC 1766 language code, it is spoken in the corresponding language,
regardless of other settings.  You can use the @code{speechd-language}
function to put the property on a string in your Elisp programs.

Another good way of using multiple languages is to use multiple
connections for separating language dependent buffers or modes, see
@ref{Multiple Connections}, and to set the @code{language} parameter
for each such a connection, see @ref{Connection Voices}.

If nothing helps better, you can select languages according to the
current input method:

@vtable @code
@item speechd-speak-input-method-languages
Alist mapping input methods to languages.  Each of the alist elements
is of the form @code{(@var{input-method-name} . @var{language})},
where @var{input-method-name} is a string naming the input method and
@var{language} is an RFC 1766 language code accepted by SSIP
(e.g. @code{en}, @code{cs}, etc.).  If the current input method is
present in the alist, the corresponding language is selected unless
overridden by another setting.
@end vtable

@node Voices, Connection Voices, Languages, Customization
@subsection Defining voices
@cindex voices
@cindex parameters

You can define special voices in speechd-el that can be used in
different situations, e.g. to speak different faces in different
voices (@pxref{Text Properties}) or to set different punctuation modes
for different kinds of buffers (@pxref{Multiple Connections}).
speechd-el voices define not only basic voice characteristics, but
also speech characteristics like pitch or rate and special properties
like punctuation reading or capital character signalization.

Voice definition is contained in the following variable:

@vtable @code
@item speechd-voices
Alist of voice identifiers and their parameters.

Each element of the list is of the form @code{(@var{voice-id}
. @var{parameters})}, where @var{voice-id} is a symbol under which the
voice will be accessed and @var{parameters} is an alist of parameter
identifiers and parameter values.  Valid parameter names are the
following symbols: @code{language}, @code{gender}, @code{age},
@code{style}, @code{name}, @code{rate}, @code{pitch}, @code{volume},
@code{punctuation-mode}, @code{capital-character-mode},
@code{message-priority}, @code{output-module}.  Please note that any
parameter entry present will change the corresponding parameter, even
if the parameter value is @code{nil} or empty; if you don't want to
change the parameter in any way by the voice, don't put it to the list
(and don't enable its entry in customize).

@code{name} value is a string identifying Speech Dispatcher voice
name.  If it is not given, the parameters @code{gender}, @code{age},
and @code{style} are considered to select a Speech Dispatcher voice.
@code{gender} value can be one of the symbols @code{male},
@code{female}, @code{neutral}.  @code{age} can be one of the symbols
@code{middle-adult}, @code{child}. @code{neutral}.  @code{style} can
be one of the numbers @code{1}, @code{2}, @code{3} (@code{style}
values are likely to be changed in future).

The @code{message-priority} parameter sets priority of any message of
the voice.  Its value is any of the message priority symbols.

See the corresponding @code{speechd-set-*} functions for valid values
of other parameters.

The voice named @code{nil} is special, it defines a default voice.
Explicit definition of its parameters is optional.
@end vtable

@node Connection Voices, Multiple Connections, Voices, Customization
@subsection Connection Voices
@cindex voices

With the help of the following variable you can let set various
connection parameters, like speech rate, language, etc.,
automatically.  speechd-el can open multiple connections according to
various criteria (@pxref{Multiple Connections}), you can set different
parameters to different connections, based on their names.

@vtable @code
@item speechd-connection-voices
Alist of connection names and corresponding voices.  Each list element
is of the form @code{(@var{connection-name} . @var{voice})}, where
@var{connection-name} is a connection name given as a string and
@var{voice} is a voice identifier defined in the variable
@code{speechd-voices}.

The default voice (named @code{nil}) is used for connections that are
not present in this variable.
@end vtable

So that changing the value of the variable could take the full effect,
the open connections must be reopened.  Unless you use the
customization interface, you must invoke the @kbd{C-u M-x
speechd-speak} command to ensure this.

There is a command to help you with setting connection voice and its
parameters:

@table @kbd
@item C-e C-a
@kindex C-e C-a
@findex speechd-add-connection-settings
Store the current connection parameters to a specified voice in the
@code{speechd-voices} variable and set that voice for the current
connection in the @code{speechd-connection-voices} variable.

Please note you are still responsible to save the variables if you
want to use them in future sessions.
@end table

@node Multiple Connections, Keys, Connection Voices, Customization
@subsection Multiple Connections
@cindex connections

You can arrange speechd-el to use separate connections to Speech
Dispatcher for certain buffers or major modes.  This is basically
useful to allow independent parameter setting for those buffers and
major modes, both by hand and through the configuration
(@pxref{Connection Voices}).

Each Speech Dispatcher connection has its unique name.  By default,
speechd-el uses a connection named @code{"default"}.  All you need to
create a separate connection is to let speechd-el choose a different
connection name in certain situations.  The process of connection name
selection is driven by the @code{speechd-speak-connections} variable.

@vtable @code
@item speechd-speak-connections
Alist mapping major modes and buffers to Speech Dispatcher
connections.  Each element of the alist is of the form
@code{(@var{mode-or-buffer} . @var{connection-name})}.

When speechd-el wants to send a message, it tests the current
environment against the @var{mode-or-buffer} entries.
@var{mode-or-buffer} may be one of the following objects, in the order
of priority from the highest to the lowest:

@itemize @bullet
@item
a list, representing a function call that should return a
non-@code{nil} value if and only if the element should be applied

@item
regular expression matching desired buffer names

@item
the symbol @code{:minibuffer}, representing minibuffers

@item
major mode symbol

@item
@code{nil}, representing non-buffer areas, e.g. echo area

@item
@code{t}, representing the default value if nothing else matches
@end itemize

If more entries match in some situation, the entry with the highest
priority is used.

@var{connection-name} is an arbitrary non-empty string naming the
corresponding connection.  If no connection with such a name is open
in the running speechd-el, it is automatically created when there's
something to send to it.

@item speechd-cancelable-connections
@cindex stop
List of names of connections that are cancelled by default when a
cancel function is called.
@end vtable

@node Keys, Braille Display Keys, Multiple Connections, Customization
@subsection Keys
@cindex keys
@cindex prefix key
@cindex key map

The command keys of speechd-el are defined by the
@code{speechd-speak-prefix} variable and the
@code{speechd-speak-mode-map} key map.

@vtable @code
@item speechd-speak-prefix
This variable defines the prefix key of the speechd-el commands, which
is @kbd{C-e} by default.  If you change the variable value after
speaking has already been started through the @code{speechd-speak}
command and you do not set it through the customization interface, you
must rerun the @code{speechd-speak} so that the change took any
effect.

@item speechd-speak-mode-map
This key map holds the mapping of the keys following the prefix key.
You can set keys here in the usual way, e.g.

@lisp
(define-key speechd-speak-mode-map "t" 'speechd-say-text)
@end lisp

to get the @code{speechd-say-text} command bound to the @code{C-e t}
key (assuming @code{C-e} is the prefix key).
@end vtable

@node Braille Display Keys, Modes, Keys, Customization
@subsection Braille Display Keys
@cindex Braille keys

When using Braille display output, speechd-el can bind actions to the
Braille display keys.  The Braille key bindings are defined in the
following variables:

@vtable @code
@item speechd-braille-key-functions
Alist of Braille display key codes and corresponding Emacs functions.
If the given key is pressed, the corresponding function is called with
a @code{speechd-brltty-driver} instance as its single argument (read
the source code for information about speechd-el output drivers).

The key codes are either integers (for BRLTTY 3.7 and older) or lists
containing three integers (for BRLTTY 3.8 and newer).  See the default
variable value for examples of possible key codes.

The assigned functions needn't be interactive.  Actually as the
functions may be invoked by asynchronous events any time at any place,
they shouldn't modify current environment in any inappropriate way.
For this reason it is recommended @emph{not} to assign user commands
to the keys here.

@file{speechd-brltty.el} contains some predefined functions that can
be assigned to the Braille display keys here:

@cindex Braille functions
@ftable @code
@item speechd-brltty-scroll-left
Scroll towards the beginning of the currently displayed message.
@item speechd-brltty-scroll-right
Scroll towards the end of the currently displayed message.
@item speechd-brltty-scroll-to-bol
Scroll to the beginning of the currently displayed message.
@item speechd-brltty-scroll-to-eol
Scroll to the end of the currently displayed message.
@item speechd-brltty-scroll-to-cursor
Scroll to the cursor position (if any) in the displayed message.
@item speechd-brltty-finish-message
Stop displaying the current message and display the next one.
@item speechd-brltty-cancel
Stop displaying the current message and discard all messages waiting
in the queue.
@item speechd-brltty-previous-message
Display the previous message from the history.
@item speechd-brltty-next-message
Display the next message from the history.
@item speechd-brltty-first-message
Display the first message in the history.
@item speechd-brltty-last-message
Display the last message in the history.
@end ftable

Additionally, the following macro is provided:

@ftable @code
@item speechd-brltty-command-key-function @var{key}
Insert function for handling @var{key} as a general input key.  This
is useful for handling Braille keys acting as general character input
keys.
@end ftable

The @code{speechd-braille-key-functions} variable contains some
default bindings initially, but as the keys and their codes differ a
lot for various Braille displays, you probably need to adjust it for
your particular device.  You can figure out the display key codes by
setting the @code{speechd-braille-show-unknown-keys} variable to
@code{t} and pressing the display keys.

@item speechd-braille-show-unknown-keys
If non-@code{nil}, show codes of the pressed Braille keys that have no
function assigned in @code{speechd-braille-key-functions}.  This is
useful to figure out the Braille key codes.
@end vtable

With BrlTTY 3.8 and higher BrlTTY can handle many braille keys itself
in X environment.  So speechd-el doesn't try to handle most keys
itself by default.  Instead it handles only keys assigned in
@code{speechd-braille-key-functions}.  If this is a problem, typically
when looking for braille key codes, the following command can be
useful:

@table @kbd
@item C-e C-b k
@kindex C-e C-b k
@findex speechd-speak-toggle-braille-keys
Toggle handling braille keys by speechd-el.  If BrlTTY handles the
keys (this is the default behavior), speechd-el receives only keys
which are assigned to commands in
@code{speechd-braille-key-functions}.  If speechd-el handles the keys,
then BrlTTY sends all the pressed keys to speechd-el without
processing them itself.
@end table

@node Modes, Debugging, Braille Display Keys, Customization
@subsection Minor mode hooks
@cindex minor modes
@cindex hooks

speechd-el provides a minor mode that enables and disables the
reading, @xref{Starting Alternative Output}.  You can let perform custom
actions on entering it through the following hook.

@vtable @code
@item speechd-speak-mode-hook
Hook run when speechd-speak minor mode is enabled.
@end vtable

@node Debugging,  , Modes, Customization
@subsection Debugging speechd-el
@cindex debugging

When you try to debug speechd-speak functions, you can experience the
problem of recursive reading in the Elisp debugger.  To avoid it, you
can instruct speechd-el to be quiet in Elisp debuggers:

@vtable @code
@item speechd-speak-in-debugger
If @code{nil}, speechd-speak functions won't be reading in Elisp debuggers.
@end vtable

@node Advanced Customization, Problems, Customization, speechd-el User Manual
@section Defining Your Own Command Feedbacks
@cindex extensions

Writing your own feedback definitions generally requires knowledge of
Elisp programming.  But don't be afraid, you can set basic things
without it, just following instructions here.

speechd-el allows you to say a text, output an icon, or call any Elisp
expression before or after a command or a function is invoked.  There
are two macros that allow you to do it, while ensuring everything is
set up properly:

@ftable @code
@item speechd-speak-command-feedback @var{command} @var{position} @var{feedback}
Install feedback invocation on @var{command}.  @code{command} is a
name of an interactive function (use @kbd{C-h C-c} to get a name of
the command bound to a given key).

@var{position} may be one of the symbols @code{before} and
@code{after} to call the feedback before or after the command is
invoked.

@code{feedback} may be a string or any Elisp expression.  If it is a
string (a text enclosed in double quotes), it defines a text to be
spoken or a sound icon to be played.  If the string starts with an
asterisk (@code{*}), it names a sound icon (the asterisk is not a part
of the name), otherwise it is a normal text.

Example:
@cindex @code{suspend-emacs}

@lisp
(speechd-speak-command-feedback suspend-emacs before "Suspending Emacs!")
@end lisp

You can put this line of Elisp code to your @file{~/.emacs} to ensure
you are informed when you invoke the @code{suspend-emacs} command
(usually bound to @kbd{C-z}).

@item speechd-speak-function-feedback @var{function} @var{position} @var{feedback}
This is the same as @code{speechd-speak-command-feedback}, except it
is called anytime the given function is invoked, whether interactively
or not.  Also, @var{function} may be any function, not only an
interactive command.
@end ftable

@emph{Please note:}

@itemize @bullet
@item
Due to Emacs deficiency, the feedback mechanism may not work on
built-in functions.

@item
Be careful if you want to install function feedbacks without help of
the macros above.  The macros install code ensuring nothing is spoken
if @code{speechd-speak-mode} is disabled and other similar
precautions.  If you do not use them, you should make those
precautions yourself.
@end itemize

@node Problems, Tips, Advanced Customization, speechd-el User Manual
@section Problems You May Encounter
@cindex problems

@itemize @bullet
@cindex Info
@item
@emph{Why are some menu items in Info not read?}

This is due the way how Emacs fontifies the menu items.  Try to set
the @code{Info-fontify-maximum-menu-size} variable to @code{0} to
avoid the problem.

@cindex appointments
@cindex diary
@item
@emph{How to make appointments read their notifications?}

Set the variable @code{appt-msg-window} to @code{nil}.  Also, adding
@code{"diary"} to the @code{speechd-speak-auto-speak-buffer} variable
may be useful.

@cindex w3m-el
@cindex URL speaking
@item
@emph{How to avoid printing URL when moving through links in w3m-el?}

Add the following code to your @file{~/.emacs}:

@lisp
(defadvice w3m-print-this-url (around my-w3m-print-this-url activate)
  (when (eq this-command 'w3m-print-this-url)
    ad-do-it))
@end lisp

@cindex TAB characters
@item
@emph{How to avoid excessive occurrences of TAB (C-i) and NL (C-j)
characters on a Braille display in some buffers
(e.g. @code{*Completion*} buffer)?}

Braille displays generally display exact content, which is usually
what you want.  But sometimes TAB characters are inserted to Emacs
buffers for the sole purpose of visual formatting.  You can tell Emacs
to suppress this behavior when possible by adding the following code
to your @file{~/.emacs}:

@lisp
(setq-default indent-tabs-mode nil)
@end lisp

@cindex repeated reading
@item
@emph{In some situations, when a modified text is read after
performing a command, the text is read in separate pieces and some of
the pieces are repeated.}

Buffer modifications can be performed by many different ways in Elisp
programs.  speechd-el is unable to track them always satisfactory.  If
you have a reasonable idea how to improve buffer modification reading,
please tell us.

As a workaround, if you encounter this problem when performing some
often used commands, you might want to define your own speaking
feedbacks of those commands.  @xref{Advanced Customization}, for more
details.

@cindex delays
@cindex garbage collection
@cindex @code{gc-cons-threshold}
@item
@emph{There are sometimes small delays (about 1 second) before
something is read after a command.}

Maybe Emacs is garbage collecting in the meantime.  Try to increase
the value of the @code{gc-cons-threshold} variable, e.g. to 4000000.
It may increase or reduce the performance, depending on your
environment and particular requirements.

If you didn't byte compile the source @file{*.el} files, do so.

If you are an experienced Elisp hacker and you can find out why
speechd-el produces significant amount of data increasing the
frequency of garbage collection and how to make the things better,
your help is welcome!

@item
@emph{During holding down the @kbd{C-n} key, the screen gets frozen
and the cursor doesn't move for a while.}

Emacs redisplay routines are generally not invoked when Emacs is busy.
speechd-el combined with your autorepeat may achieve such a state
quite easily.  If that's a real problem to you, you can reduce your
autorepeat rate or buy a faster computer.

Also, if you didn't byte compile the source @file{*.el} files, do so.

Certainly, any tips increasing speechd-el performance are welcome.
@end itemize

@node Tips, Bug Reporting, Problems, speechd-el User Manual
@section Useful Emacs tips

Don't forget that Elisp allows you to define many useful functions.
Typically, you may want to define commands reporting some information,
which can be easily identified on the Emacs screen, but which is not
so easily provided in the standard speech output interface.

Some examples:

@itemize @bullet
@item
@emph{Reporting current date in calendar:}

@cindex day in calendar
@lisp
(defun report-day ()
  (interactive)
  (message "%s" (calendar-date-string (calendar-cursor-to-date t))))
@end lisp

@item
@emph{Reporting current diary appointments:}

@cindex appointments
@lisp
(defun report-current-appointments ()
  (interactive)
  (let ((appt-now-displayed nil))
    (appt-check)))
@end lisp

@item
@emph{Reviewing ispell choices}

@cindex ispell
When you invoke the @code{ispell-word} command and the checked word is
mispelled, ispell offers you the list of alternative spellings.  You
can let speechd-el repeat the list by pressing @kbd{C-a} in the ispell
prompt.  When you want to review the choices closely, press @kbd{C-r}
to enter recursive edit and then switch to the @code{*Choices*} window
with @kbd{C-x o}.  After you review the choices, you can return back
to the ispell prompt by pressing @kbd{C-M-c}.
@end itemize

@node Bug Reporting,  , Tips, speechd-el User Manual
@section How to Report speechd-el or Speech Dispatcher Bugs
@cindex bug reporting

When you encounter a speechd-el bug, you can report it to us using the
following command.  Before doing it, please read the whole text of
this section to allow handling your bug report in a more efficient way.

@ftable @kbd
@item M-x speechd-bug
@findex speechd-bug
Report a speechd-el or Speech Dispatcher bug.  The command asks you
for some information and then asks you whether you can reproduce the
bug.  If you can, answer @kbd{y} and start reproducing the bug
immediately.  As soon as the bug is reproduced, type @kbd{C-e C-f}.
Then you can (and should) further edit the generated mail and send it
in the usual way.

@item M-x speechd-bug-reproduce
@findex speechd-bug-reproduce
@kindex C-e C-f
Start reproducing a speechd-el or Speech Dispatcher bug.  All user and
Speech Dispatcher actions are watched from this moment.

Bug reproduction is finished by pressing the @kbd{C-e C-f} keys.
After the bug reproduction is finished, information about it is
inserted into the buffer where the @code{speechd-bug-reproduce}
command was invoked.

This command is useful when you want to provide information about a
bug without generating new bug report.
@end ftable

When reporting the bugs, please always remember the following
instructions:

@itemize @bullet
@item
Write as much information about the problem as possible.  Describe
what doesn't work, what's the expected behavior, what actions have
triggered the bug, what's special about your Emacs environment or
Speech Dispatcher configuration, etc.  Don't try to analyze too much
which information is important and which is not --- everything may be
important to the developers, so try not to forget to mention anything
that might be important, better more than less.  Missing information
may cause the developers won't be able to handle the bug at all.

@item
Be as much precise as possible.  Don't expect the developers to know
the context or to know the way you typically use Emacs and speechd-el.
Write in exact terms --- instead of just writing ``when I invoke foo''
write better ``when I press the keys `M-x foo RET', thus invoking the
`foo' command''; or instead of writing ``doesn't speak what I expect''
write like ``speaks `blah blah' instead of `bleh bleh bleh' what is I
expect, since `bleh bleh bleh' is the text of the whole line''.

@item
When reproducing the bug, try to have the Speech Dispatcher logging
enabled to the highest level --- set the @code{LogLevel} option to
@code{5} in your @file{speechd.conf} configuration file.

@item
When reproducing the bug, don't do any extra actions and invoke
@kbd{C-e C-f} as soon as the bug is reproduce.  Thus you avoid losing
the relevant information of the automatically extracted log files in
an unnecessary garbage.

@item
You can also look at the Speech Dispatcher bug reporting instructions,
see @ref{Reporting Bugs,,,speechd,Speech Dispatcher}.
@end itemize

@c ****************************************************************************

@node speechd-el Elisp Library, Contact Information, speechd-el User Manual, Top
@chapter speechd-el Emacs Lisp Library

The speechd-el code can be classified into several parts:

@itemize @bullet
@item
Low-level libraries for Speech Dispatcher and BrlAPI access
implemented in the files @file{speechd.el} and @file{brltty.el}.

@item
General device independent output mechanism defined in the
@file{speechd-out.el} file.  Its particular device implementations are
in the files @file{speechd-ssip.el} and @file{speechd-brltty.el}.

@item
User interface implemented in @file{speechd-speak.el}.
@end itemize

You can use the libraries to communicate with Speech Dispatcher,
BRLTTY or other devices in your own programs.

Right now, there's no real programmer's manual to the libraries.
Please read docstrings of available variables, functions and macros.

Nevertheless, here are some instructions you can and should follow:

@itemize @bullet
@item
Don't use any functions, variables or other Lisp objects, names of
which start with prefixes separated by double dashes (such as
@code{speechd--} or @code{speechd-speak--}).  These objects are
considered private and may change incompatibly or disappear at any
time without notice.

@item
@vindex speechd-client-name
If you want to select or create a particular SSIP connection, do so by
binding the @code{speechd-client-name} variable:

@lisp
(let ((speechd-client-name "something"))
  ... the code using the connection "something" ... )
@end lisp

Please note it's usually bad idea to open two concurrent Speech
Dispatcher connections sharing the same client name.

@item
Otherwise there should be no special pitfalls and you should be safe
to do anything what makes sense.
@end itemize

You can also look at @ref{Advanced Customization}.

@c ****************************************************************************

@node Contact Information, Copying This Manual, speechd-el Elisp Library, Top
@chapter Contact Information
@cindex authors
@cindex bugs
@cindex contact

If you want to report a bug on speechd-el, send complete information
regarding the bug to the bug tracking address
@email{speechd-el@@bugs.freebsoft.org}.  If you have a patch to
speechd-el, you can send it to the same address.

@emph{Please}, before sending us any bug report, read the bug
reporting instructions, see @ref{Bug Reporting}.  Thus you allow us to
process your bug report more efficiently, resulting in a better
response to the report and faster resolving of the issue.

If you have any questions, suggestions, or anything else to tell us,
feel free to contact us at the e-mail address
@email{speechd@@freebsoft.org}.

@c ****************************************************************************

@node Copying This Manual, Index, Contact Information, Top
@appendix Copying Conditions of This Manual

@menu
* GNU Free Documentation License::  
* GNU General Public License::  
@end menu

@node GNU Free Documentation License, GNU General Public License, Copying This Manual, Copying This Manual
@section GNU Free Documentation License

@cindex FDL, GNU Free Documentation License
@center Version 1.2, November 2002

@include fdl.texi

@node GNU General Public License,  , GNU Free Documentation License, Copying This Manual
@section GNU General Public License

@cindex GPL, GNU General Public License
@center Version 3, 29 June 2007

@include gpl.texi

@c ****************************************************************************

@node Index,  , Copying This Manual, Top
@unnumbered Index

@printindex cp

@bye

@c  LocalWords:  texinfo setfilename speechd settitle syncodeindex fn cp ky vr
@c  LocalWords:  Brailcom dircategory direntry titlepage vskip pt filll dir url
@c  LocalWords:  insertcopying ifnottex cindex Elib autoload kbd findex kindex
@c  LocalWords:  pxref sexp SPC itemx var unspeak vtable xref asis alist ftable
@c  LocalWords:  docstrings minibuffers emph vindex fdl texi printindex gc foo
@c  LocalWords:  RET bleh LogLevel conf comint localhost
