brltty


BRLTTY(1)                       The BRLTTY Team                      BRLTTY(1)

NAME

       brltty - refreshable braille display driver for Linux/Unix

SYNOPSIS

       brltty [option ...]

DESCRIPTION

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

       Parameters  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 supported options are:

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

       -b driver (--braille-driver=)
              The driver for the braille display as either a two-letter driver
              identification code or the full path to the shared object.   The
              built-in default is the driver which was configured in at build-
              time.

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

       -d device (--braille-device=)
              The path to the device for accessing the braille display.  Rela-
              tive paths are anchored at /dev/.  The built-in default  is  the
              first serial port.

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

       -f file (--configuration-file=)
              The full path to the configuration file.  The  built-in  default
              is /etc/brltty.conf.

       -h (--help)
              Print a command line usage summary and exit.

       -l level (--log-level=)
              The minimum severity level for messages written to the log.  Any
              of the following numbers, or any abbreviation  of  their  corre-
              sponding 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.

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

       -p file (--preferences-file=)
              The  full path to the preferences file.  The built-in default is
              /etc/brltty-driver.prefs (where driver is the two-letter  driver
              identification code).

       -q (--quiet)
              Suppress  start-up  messages.  The default log level (see the -l
              (--log-level=) option) is changed to warning (information if  -v
              (--version) is also specified).

       -s driver (--speech-driver=)
              The  driver  for  the  speech synthesizer as either a two-letter
              driver identification code  or  the  full  path  to  the  shared
              object.  The built-in default is the driver which was configured
              in at build-time.

       -t table (--text-table=)
              The path to the text  translation  table.   Relative  paths  are
              anchored  at /etc/brltty/.  The .tbl extension is optional.  For
              simple file names, the text. prefix is optional.   The  built-in
              default is text.simple.tbl.

       -v (--version)
              Print  start-up  messages  and exit.  The default log level (see
              the -l (--log-level=) option) is changed to information.

       -B name=value,... (--braille-parameters=)
              Specify parameters for the braille display driver.

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

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

       -N (--no-speech)
              Do  not  automatically  start the speech synthesizer driver.  It
              can still be manually started with the restart speech command at
              any  time.  This option should only be used if brltty is started
              before the sound subsystem of  the  kernel  is  initialized  and
              problems with sound are encountered.

       -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 on start-up.

       -R csecs (--refresh-interval=)
              The  braille  window refresh interval in hundredths of a second.
              The built-in default is 4 (25 times per second).

       -S name=value,... (--speech-parameters=)
              Specify parameters for the speech synthesizer driver.

       -X name=value,... (--screen-parameters=)
              Specify parameters for the screen driver.

   Environment Variables
       The following environment variables are recognized if the  -E  (--envi-
       ronment-variables) option is in effect:

       BRLTTY_ATTRIBUTES_TABLE=table
              The  path  to  the attributes translation table.  Relative paths
              are anchored at /etc/brltty/.  The .tbl extension is optional.

       BRLTTY_BRAILLE_DEVICE=device
              The path to the device for accessing the braille display.  Rela-
              tive paths are anchored at /dev/.

       BRLTTY_BRAILLE_DRIVER=driver
              The driver for the braille display as either a two-letter driver
              identification code or the full path to the shared object.

       BRLTTY_BRAILLE_PARAMETERS=name=value,...
              Specify parameters for the braille display driver.

       BRLTTY_CONFIGURATION_FILE=file
              The full path to the configuration file.

       BRLTTY_CCONTRACTION_TABLE=table
              The path to the contraction table.  Relative paths are  anchored
              at /etc/brltty/.  The .ctb extension is optional.

       BRLTTY_PREFERENCES_FILE=file
              The full path to the preferences file.

       BRLTTY_SCREEN_PARAMETERS=name=value,...
              Specify parameters for the screen driver.

       BRLTTY_SPEECH_DRIVER=driver
              The  driver  for  the  speech synthesizer as either a two-letter
              driver identification code  or  the  full  path  to  the  shared
              object.

       BRLTTY_SPEECH_PARAMETERS=name=value,...
              Specify parameters for the speech synthesizer driver.

       BRLTTY_TEXT_TABLE=table
              The  path  to  the  text  translation table.  Relative paths are
              anchored at /etc/brltty/.  The .tbl extension is optional.   For
              simple file names, the text. prefix is optional.

   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  com-
       ment.

       The following configuration directives are supported:

       attributes-table table
              The  path  to  the attributes translation table.  Relative paths
              are anchored at /etc/brltty/.  The .tbl extension is optional.

       braille-device device
              The path to the device for accessing the braille display.  Rela-
              tive paths are anchored at /dev/.

       braille-driver driver
              The driver for the braille display as either a two-letter driver
              identification code or the full path to the shared object.

       braille-parameters name=value,...
              Specify parameters for the braille display driver.

       ccontraction-table table
              The path to the contraction table.  Relative paths are  anchored
              at /etc/brltty/.  The .ctb extension is optional.

       preferences-file file
              The full path to the preferences file.

       screen-parameters name=value,...
              Specify parameters for the screen driver.

       speech-driver driver
              The  driver  for  the  speech synthesizer as either a two-letter
              driver identification code  or  the  full  path  to  the  shared
              object.

       speech-parameters name=value,...
              Specify parameters for the speech synthesizer driver.

       text-table table
              The  path  to  the  text  translation table.  Relative paths are
              anchored at /etc/brltty/.  The .tbl extension is optional.   For
              simple file names, the text. prefix is optional.

brltty

NAME

SYNOPSIS

DESCRIPTION

SEE ALSO