The getty utility is called by init(8) to open and initialize the tty line, read a login name, and invoke login(1).
The argument tty is the special device file in /dev to open for the terminal (for example, ttyh0). If there is no argument or the argument is '', the tty line is assumed to be open as file descriptor 0.
The type argument can be used to make getty treat the terminal line specially. This argument is used as an index into the gettytab(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 indicated by the table located, getty will clear the terminal screen, print a banner heading, and prompt for a login name. Usually either the banner or the login prompt will include the system hostname.
Most of the default actions of getty can be circumvented, or modified, by a suitable gettytab table.
The getty utility can be set to timeout after some interval, which will cause dial up lines to hang up if the login name is not entered reasonably quickly.