    STTY(II)                     12/15/74                    STTY(II)

    NAME
         stty - set mode of typewriter

    SYNOPSIS
         (stty = 31.)
         (file descriptor in r0)
         sys stty; arg
         ...
         arg:  .byte ispeed, ospeed; .byte erase, kill; mode

         stty(fildes, arg)
         struct {
              char ispeed, ospeed;
              char erase, kill;
              int  mode;
         } *arg;

    DESCRIPTION
         Stty  sets mode bits and character speeds for the typewriter
         whose file descriptor is passed in r0 (resp.  is  the  first
         argument  to  the call).  First, the system delays until the
         typewriter is quiescent.  The input and  output  speeds  are
         set  from  the  first two bytes of the argument structure as
         indicated by the following table, which corresponds  to  the
         speeds supported by the DH-11 interface.  If DC-11, DL-11 or
         KL-11 interfaces are used, impossible speed changes are  ig-
         nored.

             0   (hang up dataphone)
             1   50 baud
             2   75 baud
             3   110 baud
             4   134.5 baud
             5   150 baud
             6   200 baud
             7   300 baud
             8   600 baud
             9   1200 baud
             10  1800 baud
             11  2400 baud
             12  4800 baud
             13  9600 baud
             14  External A
             15  External B

         In the current configuration, only 110, 150 and 300 baud are
         really supported on dial-up lines, in that the code  conver-
         sion  and  line control required for IBM 2741's (134.5 baud)
         must be implemented by the user's program, and the  half-du-
         plex  line  discipline  required  for  the 202 dataset (1200
         baud) is not supplied.

         The next two characters of the  argument  structure  specify
         the erase and kill characters respectively.  (Defaults are #

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    STTY(II)                     12/15/74                    STTY(II)

         and @.)

         The mode contains several bits which determine the  system's
         treatment of the typewriter:

              100000 Select  one  of two algorithms for backspace de-
                     lays
              040000 Select one of two algorithms for  form-feed  and
                     vertical-tab delays
              030000 Select  one  of four algorithms for carriage-re-
                     turn delays
              006000 Select one of four algorithms for tab delays
              001400 Select one of four algorithms for  new-line  de-
                     lays
              000200 even parity allowed on input (e. g. for M37s)
              000100 odd parity allowed on input
              000040 raw mode: wake up on all characters
              000020 map CR into LF; echo LF or CR as CR-LF
              000010 echo (full duplex)
              000004 map upper case to lower on input (e. g. M33)
              000002 echo and print tabs as spaces
              000001 hang  up (remove `data terminal ready,' lead CD)
                     after last close

         The delay bits specify how long transmission stops to  allow
         for mechanical or other movement when certain characters are
         sent to the terminal.  In all cases a value of  0  indicates
         no delay.

         Backspace  delays are currently ignored but will be used for
         Terminet 300's.

         If a form-feed/vertical tab delay is specified, it lasts for
         about 2 seconds.

         Carriage-return  delay type 1 lasts about .08 seconds and is
         suitable for the Terminet 300.  Delay type 2 lasts about .16
         seconds  and is suitable for the VT05 and the TI 700.  Delay
         type 3 is unimplemented and is 0.

         New-line delay type 1 is dependent on the current column and
         is  tuned for Teletype model 37's.  Type 2 is useful for the
         VT05 and is about .10 seconds.  Type 3 is unimplemented  and
         is 0.

         Tab  delay type 1 is dependent on the amount of movement and
         is tuned to the Teletype model 37.  Other types are unimple-
         mented and are 0.

         Characters  with the wrong parity, as determined by bits 200
         and 100, are ignored.

         In raw mode, every character is passed  immediately  to  the
         program  without  waiting  until a full line has been typed.
         No erase or kill processing is done; the end-of-file charac-
         ter  (EOT), the interrupt character (DEL) and the quit char-

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    STTY(II)                     12/15/74                    STTY(II)

         acter (FS) are not treated specially.

         Mode 020 causes input carriage returns  to  be  turned  into
         new-lines;  input of either CR or LF causes LF-CR both to be
         echoed (used for GE TermiNet 300's and other terminals with-
         out the newline function).

         The  hangup  mode 01 causes the line to be disconnected when
         the last process with the line open closes it or terminates.
         It is useful when a port is to be used for some special pur-
         pose; for example, if it is associated with an ACU  used  to
         place outgoing calls.

         This  system  call  is  also used with certain special files
         other than typewriters, but since none of them are  part  of
         the standard system the specifications will not be given.

    SEE ALSO
         stty(I), gtty(II)

    DIAGNOSTICS
         The error bit (c-bit) is set if the file descriptor does not
         refer to a typewriter.  From C, a negative  value  indicates
         an error.

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