1BRLTTY(1)                     The BRLTTY Project                     BRLTTY(1)
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NAME

6       brltty - refreshable braille display driver for Linux/Unix
7

SYNOPSIS

9       brltty [option ...]
10

DESCRIPTION

12       brltty  is  a  background process (daemon) which provides access to the
13       console screen (when in text mode) for a blind person using a  refresh‐
14       able braille display.  It drives the braille display, and provides com‐
15       plete screen review functionality.  Some  speech  capability  has  also
16       been incorporated.
17

OPTIONS

19       Options  can  be  passed  to  brltty in a number of ways.  From most to
20       least influential, these are:
21
22       1.  Command Line Options
23
24       2.  Boot Parameters
25
26       3.  Environment Variables (if the -E  (--environment-variables)  option
27           is in effect)
28
29       4.  The Configuration File
30
31       5.  Built-in Defaults
32
33   Command Line Options
34       The  options  are  processed  sequentially  from  left to right.  If an
35       option is specified more than once, or  in  case  of  a  conflict,  the
36       rightmost specification takes precedence.
37
38       The following options are supported:
39
40       -a table (--attributes-table=)
41              The  path  to  the attributes translation table.  Relative paths
42              are anchored at /etc/brltty/.  The .tbl extension  is  optional.
43              The built-in default is attributes.tbl.
44
45       -b driver,...|auto (--braille-driver=)
46              The  driver  for the braille display (see Driver Specification).
47              The built-in default is auto.
48
49       -c table (--contraction-table=)
50              The path to the contraction table.  Relative paths are  anchored
51              at /etc/brltty/.  The .ctb extension is optional.
52
53       -d device,... (--braille-device=)
54              The  device  to  which  the  braille  display is connected.  The
55              built-in default is usb:.
56
57              The general form of a braille  device  specification  is  quali‐
58              fier:data.  For backward compatibility with earlier releases, if
59              the qualifier is omitted then serial: is assumed.  The following
60              device types are supported:
61
62              Bluetooth
63                     For  a  bluetooth  device,  specify  bluez:address.   The
64                     address must be six two-digit hexadecimal  numbers  sepa‐
65                     rated by colons, e.g.  01:23:45:67:89:AB.
66
67              Serial For a serial device, specify serial:/path/to/device.  The
68                     serial: qualifier is optional (for  backward  compatibil‐
69                     ity).   If a relative path is given then it's anchored at
70                     /dev/ (the usual location where devices are defined on  a
71                     Unix-like  system).   The following device specifications
72                     all refer to the  primary  serial  device:  serial:/dev/,
73                     serial:, /dev/, .
74
75              USB    For  a  USB device, specify usb:.  brltty will search for
76                     the first USB device which matches  the  braille  display
77                     driver  being  used.   If this is inadequate, e.g. if you
78                     have more than one USB braille display which requires the
79                     same driver, then you can refine the device specification
80                     by appending the serial number of the display to it, e.g.
81                     usb:12345.   N.B.:  The "identification by serial number"
82                     feature doesn't work for some models because  some  manu‐
83                     facturers either don't set the USB serial number descrip‐
84                     tor at all or do set it but not to a unique value.
85
86              A comma-delimited list of braille devices may be specified.   If
87              this  is  done  then  autodetection  is performed on each listed
88              device in sequence.  This feature is particularly useful if  you
89              have  a braille display with more than one interrface, e.g. both
90              a serial and a USB port.
91
92       -e (--standard-error)
93              Write logs to standard error rather than to the system log (use‐
94              ful for debugging).
95
96       -f file (--configuration-file=)
97              The path to the configuration file.  Relative paths are anchored
98              at the current  working  directory.   The  built-in  default  is
99              /etc/brltty.conf.
100
101       -h (--help)
102              Print a command line usage summary and then exit.
103
104       -l level (--log-level=)
105              The minimum severity level for messages written to the log.  Any
106              of the following numbers, or any abbreviation  of  their  corre‐
107              sponding names, may be specified:
108
109              0   emergency
110
111              1   alert
112
113              2   critical
114
115              3   error
116
117              4   warning
118
119              5   notice
120
121              6   information
122
123              7   debug
124
125       The built-in default is notice.
126
127       -m device (--midi-device=)
128              The  device to use for the Musical Instrument Digital Interface.
129              For ALSA it's client:port, where each may be either a number  or
130              a  case-sensitive  substring  of its name.  For other interfaces
131              it's the full path to an appropriate system device.  The  built-
132              in default is:
133
134              Linux/ALSA  the first available MIDI output port
135
136              Linux/OSS   /dev/sequencer
137
138       -n (--no-daemon)
139              Remain in the foreground (useful for debugging).
140
141       -p device (--pcm-device=)
142              The  device to use for digital audio.  For ALSA it's name[:argu‐
143              ment,...].  For other interfaces it's the full path to an appro‐
144              priate system device.  The built-in default is:
145
146              FreeBSD     /dev/dsp
147
148              Linux/ALSA  hw:0,0
149
150              Linux/OSS   /dev/dsp
151
152              NetBSD      /dev/audio
153
154              OpenBSD     /dev/audio
155
156              Qnx         the preferred PCM output device
157
158              Solaris     /dev/audio
159
160       -q (--quiet)
161              Suppress  the  start-up  messages.  This is done by reducing the
162              default log level (see the -l (--log-level=) option) to  warning
163              (information  if  either -v (--verify) or -V (--version) is also
164              specified).
165
166       -r (--release-device)
167              Release the device to which the  braille  display  is  connected
168              when the current screen or window can't be read.
169
170       -s driver,...|auto (--speech-driver=)
171              The  driver  for  the  speech synthesizer (see Driver Specifica‐
172              tion).  The built-in default is auto.
173
174       -t table (--text-table=)
175              The path to the text  translation  table.   Relative  paths  are
176              anchored  at /etc/brltty/.  The .tbl extension is optional.  For
177              a simple file name, the text.  prefix is optional.  The built-in
178              default  is  text.nabcc.tbl (the North American Braille Computer
179              Code).
180
181       -v (--verify)
182              Print the start-up messages and then exit.  This always includes
183              the  versions  of brltty itself, the server side of its applica‐
184              tion programming interface, and each of the selected braille and
185              speech drivers.  If the -q (--quiet) option isn't also specified
186              then it also includes  the  values  of  the  options  after  all
187              sources  have  been considered.  If more than one braille driver
188              and/or more than one braille  device  has  been  specified  then
189              braille  display  autodetection  is performed.  If more than one
190              speech driver has been specified then speech synthesizer autode‐
191              tection is performed.
192
193       -x driver (--screen-driver=)
194              The  screen  driver.   The  built-in default is operating system
195              appropriate.
196
197       -A name=value,... (--api-parameters=)
198              Parameters for the application programming  interface.   If  the
199              same  parameter  is  specified more than once then the rightmost
200              specification is used.  Parameter names may be abbreviated.
201
202       -B [driver:]name=value,... (--braille-parameters=)
203              Parameters for the braille display driver.  If the same  parame‐
204              ter is specified more than once then the rightmost specification
205              is used.  Parameter names may be abbreviated.   If  a  parameter
206              assignment  is  qualified with a driver identification code then
207              it's only processed if that  braille  display  driver  is  being
208              used.
209
210       -E (--environment-variables)
211              Recognize environment variables.
212
213       -F fifo (--speech-fifo=)
214              The  FIFO  which  gives  other  applications  access to brltty's
215              speech driver.  It's created at start-up and removed at termina‐
216              tion.   Relative paths are anchored at /etc/brltty/.  The built-
217              in default is that no FIFO is created.
218
219       -M csecs (--message-delay=)
220              The message hold time in hundredths of a second.   The  built-in
221              default is 400 (4 seconds).
222
223       -N (--no-api)
224              Don't start the application programming interface.
225
226       -P file (--pid-file=)
227              The full path to the process identifier file.  If this option is
228              supplied, brltty writes its process identifier  (pid)  into  the
229              specified  file  at  start-up.   The file is removed when brltty
230              terminates.
231
232       -S [driver:]name=value,... (--speech-parameters=)
233              Parameters for the  speech  synthesizer  driver.   If  the  same
234              parameter  is specified more than once then the rightmost speci‐
235              fication is used.  Parameter names may  be  abbreviated.   If  a
236              parameter  assignment  is qualified with a driver identification
237              code then it's only processed if that speech synthesizer  driver
238              is being used.
239
240       -U csecs (--update-interval=)
241              The  braille  window  update interval in hundredths of a second.
242              The built-in default is 4 (25 times per second).
243
244       -V (--version)
245              Print the versions of brltty itself,  the  server  side  of  its
246              application  programming interface, and those drivers which were
247              configured in at build-time, and then exit.  If the -q (--quiet)
248              option  isn't  also specified then also print copyright informa‐
249              tion.
250
251       -X name=value,... (--screen-parameters=)
252              Parameters for the screen driver.   If  the  same  parameter  is
253              specified  more  than  once  then the rightmost specification is
254              used.  Parameter names may be abbreviated.
255
256   Environment Variables
257       The following environment variables are recognized if the  -E  (--envi‐
258       ronment-variables) option is specified:
259
260       BRLTTY_API_PARAMETERS=name=value,...
261              Parameters  for  the application programming interface.  See the
262              -A (--api-parameters=) option for details.
263
264       BRLTTY_ATTRIBUTES_TABLE=table
265              The attributes translation table.  See the -a  (--attributes-ta‐
266              ble=) option for details.
267
268       BRLTTY_BRAILLE_DEVICE=device,...
269              The  device  to which the braille display is connected.  See the
270              -d (--braille-device=) option for details.
271
272       BRLTTY_BRAILLE_DRIVER=driver,...|auto
273              The driver for the braille  display.   See  the  -b  (--braille-
274              driver=) option for details.
275
276       BRLTTY_BRAILLE_PARAMETERS=[driver:]name=value,...
277              Parameters   for   the  braille  display  driver.   See  the  -B
278              (--braille-parameters=) option for details.
279
280       BRLTTY_CONFIGURATION_FILE=file
281              The configuration  file.   See  the  -f  (--configuration-file=)
282              option for details.
283
284       BRLTTY_CONTRACTION_TABLE=table
285              The contraction table.  See the -c (--contraction-table=) option
286              for details.
287
288       BRLTTY_MIDI_DEVICE=device
289              The device to use for the Musical Instrument Digital  Interface.
290              See the -m (--midi-device=) option for details.
291
292       BRLTTY_PCM_DEVICE=device
293              The device to use for digital audio.  See the -p (--pcm-device=)
294              option for details.
295
296       BRLTTY_RELEASE_DEVICE=on|off
297              Release the device to which the  braille  display  is  connected
298              when  the  current  screen  or window can't be read.  See the -r
299              (--release-device) option for details.
300
301       BRLTTY_SCREEN_DRIVER=driver
302              The screen driver.  See the  -x  (--screen-driver=)  option  for
303              details.
304
305       BRLTTY_SCREEN_PARAMETERS=name=value,...
306              Parameters  for the screen driver.  See the -X (--screen-parame‐
307              ters=) option for details.
308
309       BRLTTY_SPEECH_DRIVER=driver,...|auto
310              The driver for the speech synthesizer.  See  the  -s  (--speech-
311              driver=) option for details.
312
313       BRLTTY_SPEECH_FIFO=fifo
314              The  FIFO  which  gives  other  applications  access to brltty's
315              speech driver.  See the -F (--speech-fifo=) option for details.
316
317       BRLTTY_SPEECH_PARAMETERS=[driver:]name=value,...
318              Parameters for  the  speech  synthesizer  driver.   See  the  -S
319              (--speech-parameters=) option for details.
320
321       BRLTTY_TEXT_TABLE=table
322              The  text  translation table.  See the -t (--text-table=) option
323              for details.
324
325   The Configuration File
326       Blank lines are ignored.  If the character # occurs on  any  line  then
327       all  characters  from  it to the end of that line are treated as a com‐
328       ment.
329
330       The following configuration directives are supported:
331
332       api-parameters name=value,...
333              Parameters for the application programming interface.   See  the
334              -A (--api-parameters=) option for details.
335
336       attributes-table table
337              The  attributes translation table.  See the -a (--attributes-ta‐
338              ble=) option for details.
339
340       braille-device device,...
341              The device to which the braille display is connected.   See  the
342              -d (--braille-device=) option for details.
343
344       braille-driver driver,...|auto
345              The  driver  for  the  braille  display.  See the -b (--braille-
346              driver=) option for details.
347
348       braille-parameters [driver:]name=value,...
349              Parameters  for  the  braille  display  driver.   See   the   -B
350              (--braille-parameters=) option for details.
351
352       contraction-table table
353              The contraction table.  See the -c (--contraction-table=) option
354              for details.
355
356       midi-device device
357              The device to use for the Musical Instrument Digital  Interface.
358              See the -m (--midi-device=) option for details.
359
360       pcm-device device
361              The device to use for digital audio.  See the -p (--pcm-device=)
362              option for details.
363
364       release-device on|off
365              Release the device to which the  braille  display  is  connected
366              when  the  current  screen  or window can't be read.  See the -r
367              (--release-device) option for details.
368
369       screen-driver driver
370              The screen driver.  See the  -x  (--screen-driver=)  option  for
371              details.
372
373       screen-parameters name=value,...
374              Parameters  for the screen driver.  See the -X (--screen-parame‐
375              ters=) option for details.
376
377       speech-driver driver,...|auto
378              The driver for the speech synthesizer.  See  the  -s  (--speech-
379              driver=) option for details.
380
381       speech-fifo fifo
382              The  FIFO  which  gives  other  applications  access to brltty's
383              speech driver.  See the -F (--speech-fifo=) option for details.
384
385       speech-parameters [driver:]name=value,...
386              Parameters for  the  speech  synthesizer  driver.   See  the  -S
387              (--speech-parameters=) option for details.
388
389       text-table table
390              The  text  translation table.  See the -t (--text-table=) option
391              for details.
392
393   Driver Specification
394       A braille display or speech synthesizer driver must  be  specified  via
395       its identification code:
396
397              al  Alva
398
399              at  Albatross
400
401              ba  BrlAPI
402
403              bd  Braudi
404
405              bl  BrailleLite
406
407              bm  Baum
408
409              bn  BrailleNote
410
411              cb  CombiBraille
412
413              ec  EcoBraille
414
415              es  ExternalSpeech
416
417              eu  EuroBraille
418
419              fl  FestivalLite
420
421              fs  FreedomScientific
422
423              fv  Festival
424
425              gs  GenericSay
426
427              ht  HandyTech
428
429              il  IrisLinux
430
431              lb  Libbraille
432
433              lt  LogText
434
435              mb  MultiBraille
436
437              md  MDV
438
439              mn  MiniBraille
440
441              mp  Mikropuhe
442
443              no  no driver
444
445              pm  Papenmeier
446
447              sd  SpeechDispatcher
448
449              sw  Swift
450
451              th  Theta
452
453              tn  TechniBraille Systems Inc.
454
455              ts  Telesensory Systems Inc.
456
457              tt  TTY
458
459              vd  VideoBraille
460
461              vo  Voyager
462
463              vr  Virtual
464
465              vs  VisioBraille
466
467              vv  ViaVoice
468
469              xw  XWindow
470
471              A  comma-delimited list of drivers may be specified.  If this is
472              done then autodetection is performed using each listed driver in
473              sequence.   You may need to experiment in order to determine the
474              most reliable order since some drivers  autodetect  better  than
475              others.
476
477              If  the single word auto is specified then autodetection is per‐
478              formed using only those drivers which are known to  be  reliable
479              for this purpose.
480

SEE ALSO

482       For    full    documentation,    see   brltty's   on-line   manual   at
483       [http://mielke.cc/brltty/doc/Manual-HTML/Manual.html].
484
485
486
487brltty 3.8                         June 2007                         BRLTTY(1)
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