xenial (1) brltty.1.gz

Provided by: brltty_5.3.1-2ubuntu2.1_amd64 bug

NAME

       brltty - refreshable braille display driver for Linux/Unix

SYNOPSIS

       brltty [option ...]

DESCRIPTION

       brltty  is  a background process (daemon) which provides access to the console screen (when in text mode)
       for a blind person using a refreshable braille display.  It drives  the  braille  display,  and  provides
       complete screen review functionality.  Some speech capability has also been incorporated.

OPTIONS

       Options can be passed to brltty in a number of ways.  From most to least influential, these are:

       1.  Command Line Options

       2.  Boot Parameters

       3.  Environment Variables (if the -E (--environment-variables) option is in effect)

       4.  The Configuration File

       5.  Built-in Defaults

   Command Line Options
       The  options are processed sequentially from left to right.  If an option is specified more than once, or
       in case of a conflict, the rightmost specification takes precedence.

       The following options are supported:

       -a table (--attributes-table=)
              The path to the attributes table.  Relative paths are  anchored  at  /etc/brltty/Attributes.   The
              .atb extension is optional.  The built-in default is left_right.atb.

       -b driver,...|auto (--braille-driver=)
              The driver for the braille display (see Driver Specification).  The built-in default is auto.

       -c table (--contraction-table=)
              The  path  to the contraction table.  Relative paths are anchored at /etc/brltty/Contraction.  The
              .ctb extension is optional.

       -d device,... (--braille-device=)
              The device to which the braille display is connected.  The built-in default is usb:.

              The general form of a braille device specification is qualifier:data.  For backward  compatibility
              with  earlier releases, if the qualifier is omitted then serial: is assumed.  The following device
              types are supported:

              Bluetooth
                     For a  bluetooth  device,  specify  bluez:address.   The  address  must  be  six  two-digit
                     hexadecimal numbers separated by colons, e.g.  01:23:45:67:89:AB.

              Serial For  a  serial  device,  specify serial:/path/to/device.  The serial: qualifier is optional
                     (for backward compatibility).  If a relative path is given then it's anchored at /dev/ (the
                     usual  location  where  devices  are  defined on a Unix-like system).  The following device
                     specifications all refer to the primary  serial  device:  serial:/dev/ttyS0,  serial:ttyS0,
                     /dev/ttyS0, ttyS0.

              USB    For  a USB device, specify usb:.  brltty will search for the first USB device which matches
                     the braille display driver being used.  If this is inadequate, e.g. if you have  more  than
                     one  USB  braille  display  which  requires the same driver, then you can refine the device
                     specification by appending the serial number of the display to it, e.g.  usb:12345.   N.B.:
                     The  "identification  by  serial  number" feature doesn't work for some models because some
                     manufacturers either don't set the USB serial number descriptor at all or do set it but not
                     to a unique value.

              A comma-delimited list of braille devices may be specified.  If this is done then autodetection is
              performed on each listed device in sequence.  This feature is particularly useful if  you  have  a
              braille display with more than one interface, e.g. both a serial and a USB port.

       -e (--standard-error)
              Write logs to standard error rather than to the system log (useful for debugging).

       -f file (--configuration-file=)
              The path to the configuration file.  Relative paths are anchored at the current working directory.
              The built-in default is /etc/brltty.conf.

       -h (--help)
              Print a command line usage summary (commonly used options only), and then exit.

       -i name (--speech-input=)
              The file system object (FIFO, named pipe, named socket, etc) which gives other applications access
              to  brltty's speech driver for text-to-speech conversion.  It's created at start-up and removed at
              termination.  Relative paths are anchored at the current working directory.  The built-in  default
              is that the file system object is not created.

       -k table (--keyboard-table=)
              The  path  to  the keyboard table.  Relative paths are anchored at /etc/brltty/Keyboard.  The .ktb
              extension is optional.

       -l level (--log-level=)
              The minimum severity level for messages written to the log.  Any of the following numbers, or  any
              abbreviation of their corresponding names, may be specified:

              0   emergency

              1   alert

              2   critical

              3   error

              4   warning

              5   notice

              6   information

              7   debug

       The built-in default is notice.

       -m device (--midi-device=)
              The  device to use for the Musical Instrument Digital Interface.  For ALSA it's client:port, where
              each may be either a number or a case-sensitive substring of its name.  For other interfaces  it's
              the full path to an appropriate system device.  The built-in default is:

              Linux/ALSA  the first available MIDI output port

              Linux/OSS   /dev/sequencer

       -n (--no-daemon)
              Remain in the foreground (useful for debugging).

       -p device (--pcm-device=)
              The  device  to  use  for digital audio.  For ALSA it's name[:argument,...].  For other interfaces
              it's the full path to an appropriate system device.  The built-in default is:

              FreeBSD     /dev/dsp

              Linux/ALSA  hw:0,0

              Linux/OSS   /dev/dsp

              NetBSD      /dev/audio

              OpenBSD     /dev/audio

              Qnx         the preferred PCM output device

              Solaris     /dev/audio

       -q (--quiet)
              Suppress the start-up messages.  This is done by reducing  the  default  log  level  (see  the  -l
              (--log-level=)  option)  to warning (information if either -v (--verify) or -V (--version) is also
              specified).

       -r (--release-device)
              Release the device to which the braille display is connected when the  current  screen  or  window
              can't be read.

       -s driver,...|auto (--speech-driver=)
              The driver for the speech synthesizer (see Driver Specification).  The built-in default is auto.

       -t table (--text-table=)
              The  path to the text table.  Relative paths are anchored at /etc/brltty/Text.  The .ttb extension
              is optional.  The built-in default is en-nabcc.ttb (the North American Braille Computer Code).

       -v (--verify)
              Print the start-up messages and then exit.  This always includes the versions  of  brltty  itself,
              the  server  side  of  its application programming interface, and each of the selected braille and
              speech drivers.  If the -q (--quiet) option isn't also specified then it also includes the  values
              of  the  options  after  all sources have been considered.  If more than one braille driver and/or
              more than one braille device has been specified then braille display autodetection  is  performed.
              If  more  than  one  speech  driver  has  been  specified then speech synthesizer autodetection is
              performed.

       -x driver (--screen-driver=)
              The screen driver.  The built-in default is operating system appropriate.

       -A name=value,... (--api-parameters=)
              Parameters for the application programming interface.  If the same  parameter  is  specified  more
              than once then the rightmost specification is used.  Parameter names may be abbreviated.

       -B [driver:]name=value,... (--braille-parameters=)
              Parameters for the braille display driver.  If the same parameter is specified more than once then
              the rightmost specification is  used.   Parameter  names  may  be  abbreviated.   If  a  parameter
              assignment is qualified with a driver identification code then it's only processed if that braille
              display driver is being used.

       -D directory (--drivers-directory=)
              The path to the directory which contains the dynamically loadable driver  objects.   The  built-in
              default is /lib/brltty.

       -E (--environment-variables)
              Recognize environment variables.

       -F file (--preferences-file=)
              The  path  to the preferences file.  Relative paths are anchored at /var/lib/brltty.  The built-in
              default is brltty.prefs.

       -H (--full-help)
              Print a command line usage summary (all options), and then exit.

       -I (--install-service)
              (Windows only) Install brltty as the BrlAPI service so that it will be automatically started  when
              the system is booted, and so that applications can know that a BrlAPI server is running.

       -K arg (--keyboard-properties=)
              Properties of the keyboard.

       -L file (--log-file=)
              The  file  to  which log messages are written.  Relative paths are anchored at the current working
              directory.  The default is to send log messages to the system log.

       -M csecs (--message-delay=)
              The message hold time in hundredths of a second.  The built-in default is 400 (4 seconds).

       -N (--no-api)
              Don't start the application programming interface.

       -P file (--pid-file=)
              The full path to the process identifier file.  If this  option  is  supplied,  brltty  writes  its
              process  identifier  (pid)  into  the specified file at start-up.  The file is removed when brltty
              terminates.

       -R (--remove-service)
              (Windows only) Remove the BrlAPI service so that brltty will not be automatically started when the
              system is booted, and so that applications can know that no BrlAPI server is running.

       -S [driver:]name=value,... (--speech-parameters=)
              Parameters  for  the speech synthesizer driver.  If the same parameter is specified more than once
              then the rightmost specification is used.  Parameter names may be  abbreviated.   If  a  parameter
              assignment  is qualified with a driver identification code then it's only processed if that speech
              synthesizer driver is being used.

       -T directory (--tables-directory=)
              The path to the directory which contains the text, attributes, contraction,  keyboard,  and  input
              tables.  The built-in default is /etc/brltty.

       -U directory (--updatable-directory=)
              The  path  to  a  directory  which  contains  files  that can be updated.  The built-in default is
              /var/lib/brltty.

       -V (--version)
              Print the versions of brltty itself, the server side of its application programming interface, and
              those  drivers  which were configured in at build-time, and then exit.  If the -q (--quiet) option
              isn't also specified then also print copyright information.

       -W directory (--writable-directory=)
              The path to a directory which can be written to.  The built-in default is /var/run/brltty.

       -X name=value,... (--screen-parameters=)
              Parameters for the screen driver.  If the same parameter is specified  more  than  once  then  the
              rightmost specification is used.  Parameter names may be abbreviated.

   Environment Variables
       The  following  environment  variables  are  recognized  if  the  -E  (--environment-variables) option is
       specified:

       BRLTTY_API_PARAMETERS=name=value,...
              Parameters for the application programming interface.  See the -A (--api-parameters=)  option  for
              details.

       BRLTTY_ATTRIBUTES_TABLE=table
              The attributes table.  See the -a (--attributes-table=) option for details.

       BRLTTY_BRAILLE_DEVICE=device,...
              The  device  to which the braille display is connected.  See the -d (--braille-device=) option for
              details.

       BRLTTY_BRAILLE_DRIVER=driver,...|auto
              The driver for the braille display.  See the -b (--braille-driver=) option for details.

       BRLTTY_BRAILLE_PARAMETERS=[driver:]name=value,...
              Parameters for the braille display driver.  See the -B (--braille-parameters=) option for details.

       BRLTTY_CONFIGURATION_FILE=file
              The configuration file.  See the -f (--configuration-file=) option for details.

       BRLTTY_CONTRACTION_TABLE=table
              The contraction table.  See the -c (--contraction-table=) option for details.

       BRLTTY_MIDI_DEVICE=device
              The device to use for the Musical Instrument  Digital  Interface.   See  the  -m  (--midi-device=)
              option for details.

       BRLTTY_PCM_DEVICE=device
              The device to use for digital audio.  See the -p (--pcm-device=) option for details.

       BRLTTY_PREFERENCES_FILE=file
              The preferences file.  See the -F (--preferences-file=) option for details.

       BRLTTY_RELEASE_DEVICE=on|off
              Release  the  device  to  which the braille display is connected when the current screen or window
              can't be read.  See the -r (--release-device) option for details.

       BRLTTY_SCREEN_DRIVER=driver
              The screen driver.  See the -x (--screen-driver=) option for details.

       BRLTTY_SCREEN_PARAMETERS=name=value,...
              Parameters for the screen driver.  See the -X (--screen-parameters=) option for details.

       BRLTTY_SPEECH_DRIVER=driver,...|auto
              The driver for the speech synthesizer.  See the -s (--speech-driver=) option for details.

       BRLTTY_SPEECH_INPUT=name
              The file system object which gives other applications access to brltty's speech driver  for  text-
              to-speech conversion.  See the -i (--speech-input=) option for details.

       BRLTTY_SPEECH_PARAMETERS=[driver:]name=value,...
              Parameters  for  the  speech  synthesizer  driver.   See  the -S (--speech-parameters=) option for
              details.

       BRLTTY_TEXT_TABLE=table
              The text table.  See the -t (--text-table=) option for details.

   The Configuration File
       Blank lines are ignored.  If the character # occurs on any line then all characters from it to the end of
       that line are treated as a comment.

       The following configuration directives are supported:

       api-parameters name=value,...
              Parameters  for  the application programming interface.  See the -A (--api-parameters=) option for
              details.

       attributes-table table
              The attributes table.  See the -a (--attributes-table=) option for details.

       braille-device device,...
              The device to which the braille display is connected.  See the -d (--braille-device=)  option  for
              details.

       braille-driver driver,...|auto
              The driver for the braille display.  See the -b (--braille-driver=) option for details.

       braille-parameters [driver:]name=value,...
              Parameters for the braille display driver.  See the -B (--braille-parameters=) option for details.

       contraction-table table
              The contraction table.  See the -c (--contraction-table=) option for details.

       midi-device device
              The  device  to  use  for  the  Musical Instrument Digital Interface.  See the -m (--midi-device=)
              option for details.

       pcm-device device
              The device to use for digital audio.  See the -p (--pcm-device=) option for details.

       preferences-file file
              The preferences file.  See the -F (--preferences-file=) option for details.

       release-device on|off
              Release the device to which the braille display is connected when the  current  screen  or  window
              can't be read.  See the -r (--release-device) option for details.

       screen-driver driver
              The screen driver.  See the -x (--screen-driver=) option for details.

       screen-parameters name=value,...
              Parameters for the screen driver.  See the -X (--screen-parameters=) option for details.

       speech-driver driver,...|auto
              The driver for the speech synthesizer.  See the -s (--speech-driver=) option for details.

       speech-input 0me
              The  file  system  object  which  gives  other  applications  access to brltty's speech driver for
              text-to-speech conversion.  See the -i (--speech-input=) option for details.

       speech-parameters [driver:]name=value,...
              Parameters for the speech synthesizer  driver.   See  the  -S  (--speech-parameters=)  option  for
              details.

       text-table table
              The text table.  See the -t (--text-table=) option for details.

   Driver Specification
       A braille display or speech synthesizer driver must be specified via its identification code:

              al  Alva

              an  Android

              at  Albatross

              ba  BrlAPI

              bc  BrailComm

              bd  Braudi

              bg  B2G

              bl  BrailleLite

              bm  Baum

              bn  BrailleNote

              cb  CombiBraille

              ec  EcoBraille

              es  eSpeak

              eu  EuroBraille

              fl  FestivalLite

              fs  FreedomScientific

              fv  Festival

              gs  GenericSay

              hd  Hedo

              hm  HIMS

              ht  HandyTech

              hw  HumanWare

              ir  Iris

              lb  Libbraille

              lt  LogText

              mb  MultiBraille

              md  MDV

              mm  BrailleMemo

              mn  MiniBraille

              mp  Mikropuhe

              mt  Metec

              no  no driver

              np  NinePoint

              pg  Pegasus

              pm  Papenmeier

              sd  SpeechDispatcher

              sk  Seika

              sw  Swift

              th  Theta

              tn  TechniBraille Systems Inc.

              ts  Telesensory Systems Inc.

              tt  TTY

              vd  VideoBraille

              vo  Voyager, Part232 (serial adapter), BraillePen/EasyLink

              vr  Virtual

              vs  VisioBraille

              vv  ViaVoice

              xs  ExternalSpeech

              xw  XWindow

              A  comma-delimited  list  of  drivers  may  be  specified.   If this is done then autodetection is
              performed using each listed driver in sequence.  You may need to experiment in order to  determine
              the most reliable order since some drivers autodetect better than others.

              If  the  single  word  auto  is specified then autodetection is performed using only those drivers
              which are known to be reliable for this purpose.

SEE ALSO

       For full documentation, see brltty's on-line manual at [http://brltty.com/documentation.html].