GETTY(8)	    UNIX Programmer's Manual		 GETTY(8)



NAME
     getty  - set terminal mode

SYNOPSIS
     getty [ type [ tty ] ]

DESCRIPTION
     _G_e_t_t_y is usually invoked by _i_n_i_t(8) to open and initialize
     the tty line, read a login name, and invoke _l_o_g_i_n(1).  _g_e_t_t_y
     attempts to adapt the system to the speed and type of termi-
     nal being used.

     The argument _t_t_y is the special device file in /dev to open
     for the terminal (e.g., ``ttyh0'').  If there is no argument
     or the argument is ``-'', the tty line is assumed to be open
     as file descriptor 0.

     The _t_y_p_e argument can be used to make _g_e_t_t_y treat the termi-
     nal line specially.  This argument is used as an index into
     the _g_e_t_t_y_t_a_b(5) database, to determine the characteristics
     of the line.  If there is no argument, or there is no such
     table, the default table is used.	If there is no
     /etc/gettytab a set of system defaults is used.  If indi-
     cated by the table located, _g_e_t_t_y will clear the terminal
     screen, print a banner heading, and prompt for a login name.
     Usually either the banner of the login prompt will include
     the system hostname.  Then the user's name is read, a char-
     acter 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 usually then changed and
     the `login:' is typed again; a second `break' changes the
     speed again and the `login:' is typed once more.  Successive
     `break' characters cycle through the same standard set of
     speeds.

     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 _t_t_y(4)).

     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, _l_o_g_i_n is called with the user's name as an argu-
     ment.

     Most of the default actions of _g_e_t_t_y can be circumvented, or
     modified, by a suitable _g_e_t_t_y_t_a_b table.

     _G_e_t_t_y can be set to timeout after some interval, which will
     cause dial up lines to hang up if the login name is not



Printed 11/26/99	November 17, 1996			1






GETTY(8)	    UNIX Programmer's Manual		 GETTY(8)



     entered reasonably quickly.

DIAGNOSTICS
     _t_t_y_x_x: No such device or address.	_t_t_y_x_x: No such file or
     address.  A terminal which is turned on in the _t_t_y_s file
     cannot be opened, likely because the requisite lines are
     either not configured into the system, the associated device
     was not attached during boot-time system configuration, or
     the special file in /dev does not exist.

FILES
     /etc/gettytab

SEE ALSO
     gettytab(5), init(8), login(1), ioctl(2), tty(4), ttys(5)








































Printed 11/26/99	November 17, 1996			2