GETTY(VIII)                  2/11/75                  GETTY(VIII)


     getty  - set typewriter mode


     /etc/getty [ char ]


     Getty  is  invoked  by  init  (VIII)  immediately  after   a

     typewriter  is  opened  following  a  dial-up.  It reads the

     user's name and invokes the login command (I) with the  name

     as argument.  While reading the name getty attempts to adapt

     the system to the speed and type of terminal being used.

     Init calls getty with an argument specified by the ttys file

     entry for the typewriter line.  Arguments other than `0' can

     be used to make getty treat the line  specially.   Normally,

     it  sets  the  speed of the interface to 300 baud, specifies

     that raw mode is to be used (break on every character), that

     echo  is  to  be  suppressed, and either parity allowed.  It

     types the ``login:'' message, which includes the  characters

     which  put  the  Terminet  300 terminal into full-duplex and

     return the GSI  terminal  to  non-graphic  mode.   Then  the

     user's  name  is  read,  a  character  at a time.  If a null

     character is received, it is assumed to be the result of the

     user  pushing  the ``break'' (``interrupt'') key.  The speed

     is then changed to 150 baud  and  the  ``login:''  is  typed

     again, this time including the character sequence which puts

     a Teletype  37  into  full-duplex.   If  a  subsequent  null

     character  is  received,  the  speed  is changed back to 300


     The user's name is terminated by  a  new-line  or  carriage-

     return  character.   The  latter results in the system being

     set to treat carriage returns appropriately (see stty (II)).

     The user's name is scanned to see if it contains any  lower-

     case  alphabetic  characters;  if  not,  and  if the name is

     nonempty, the system is told to map  any  future  upper-case

     characters into the corresponding lower-case characters.

     Finally, login is called with the user's name as argument.


     init (VIII), login (I), stty (II), ttys (V)