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ttys(5) [bsd man page]

TTYS(5) 							File Formats Manual							   TTYS(5)

NAME
ttys - terminal initialization data DESCRIPTION
The ttys file contains information that is used by various routines to initialize and control the use of terminal special files. This information is read with the getttyent(3) library routines. There is one line in the ttys file per special file. Fields are separated by tabs and/or spaces. Some fields may contain more than one word and should be enclosed in double quotes. Blank lines and comments can appear anywhere in the file; comments are delimited by `#' and new line. Unspecified fields default to null. The first field is the termi- nal's entry in the device directory, /dev. The second field of the file is the command to execute for the line, typically getty(8), which performs such tasks as baud-rate recognition, reading the login name, and calling login(1). It can be, however, any desired command, for example the start up for a window system terminal emulator or some other daemon process, and can contain multiple words if quoted. The third field is the type of terminal normally connected to that tty line, as found in the termcap(5) data base file. The remaining fields set flags in the ty_status entry (see getttyent(3)) or specify a window system process that init(8) will maintain for the terminal line. As flag values, the strings `on' and `off' specify whether init should execute the command given in the second field, while `secure' in addition to `on' allows root to login on this line. These flag fields should not be quoted. The string `window=' is followed by a quoted command string which init will execute before starting getty. If the line ends in a comment, the comment is included in the ty_comment field of the ttyent structure. Some examples: console "/usr/libexec/getty std.1200" vt100 on secure ttyd0 "/usr/libexec/getty d1200" dialup on # 555-1234 ttyh0 "/usr/libexec/getty std.9600" hp2621-nl on # 254MC ttyh1 "/usr/libexec/getty std.9600" plugboard on # John's office ttyp0 none network ttyp1 none network off ttyv0 "/usr/new/xterm -L :0" vs100 on window="/usr/new/Xvs100 0" The first example permits root login on the console at 1200 baud, the second allows dialup at 1200 baud without root login, the third and fourth allow login at 9600 baud with terminal types of "hp2621-nl" and "plugboard" respectively, the fifth and sixth line are examples of network pseudo ttys, which should not have getty enabled on them, and the last example shows a terminal emulator and window system startup entry. FILES
/etc/ttys SEE ALSO
login(1), getttyent(3), gettytab(5), init(8), getty(8) 7th Edition November 16, 1996 TTYS(5)

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TTYS(5) 						      BSD File Formats Manual							   TTYS(5)

NAME
ttys -- terminal initialization information DESCRIPTION
The file ttys contains information that is used by various routines to initialize and control the use of terminal special files. Pseudo-ter- minals (see pts(4)) are not listed. This information is read with the getttyent(3) library routines. There is one line in the ttys file per special device file. Fields are separated by tabs and/or spaces. Fields comprised of more than one word should be enclosed in double quotes (``"''). Blank lines and comments may appear anywhere in the file; comments are delimited by hash marks (``#'') and new lines. Any unspeci- fied fields will default to null. The first field is normally the name of the terminal special file as it is found in /dev. However, it can be any arbitrary string when the associated command is not related to a tty. The second field of the file is the command to execute for the line, usually getty(8), which initializes and opens the line, setting the speed, waiting for a user name and executing the login(1) program. It can be, however, any desired command, for example the start up for a window system terminal emulator or some other daemon process, and can contain multiple words if quoted. The third field is the type of terminal usually connected to that tty line, normally the one found in the termcap(5) data base file. The environment variable TERM is initialized with the value by either getty(8) or login(1). The remaining fields set flags in the ty_status entry (see getttyent(3)), specify a window system process that init(8) will maintain for the terminal line, optionally determine the type of tty (whether dialin, network or otherwise), or specify a tty group name that allows the login class database (see login.conf(5)) to refer to many ttys as a group, to selectively allow or deny access or enable or disable accounting facilities for ttys as a group. As flag values, the strings ``on'' and ``off'' specify that init(8) should (should not) execute the command given in the second field. ``onifconsole'' will cause this line to be enabled if and only if it is an active kernel console device (it is equivalent to ``on'' in this case). The flag ``secure'' (if the console is enabled) allows users with a uid of 0 to login on this line. The flag ``dialin'' indicates that a tty entry describes a dialin line, and ``network'' is obsolete and does nothing. Either of these strings may also be specified in the terminal type field. The string ``window='' may be followed by a quoted command string which init(8) will execute before starting the com- mand specified by the second field. The string ``group='' may be followed by a group name comprised of alphanumeric characters that can be used by login.conf(5) to refer to many tty lines as a group to enable or disable access and accounting facilities. If no group is specified, then the tty becomes a member of the group "none". For backwards compatibility, the ``group='' should appear last on the line, immediately before the optional comment. Both the second field and any command specified with ``window='' will be split into words and executed using execve(2). Words are separated by any combinations of tabs and spaces. Arguments containing whitespace should be enclosed in single quotes ('). Note that no shell-style globbing or other variable substitution occurs. FILES
/etc/ttys EXAMPLES
# root login on console at 1200 baud console "/usr/libexec/getty std.1200" vt100 on secure # dialup at 1200 baud, no root logins ttyd0 "/usr/libexec/getty d1200" dialup on group=dialup # 555-1234 # Mike's terminal: hp2621 ttyh0 "/usr/libexec/getty std.9600" hp2621-nl on group=dialup # 457 Evans # John's terminal: vt100 ttyh1 "/usr/libexec/getty std.9600" vt100 on group=dialup # 459 Evans # terminal emulate/window system ttyv0 "/usr/local/bin/xterm -display :0" xterm on window="/usr/local/bin/X :0" SEE ALSO
login(1), getttyent(3), gettytab(5), login.conf(5), termcap(5), getty(8), init(8) HISTORY
A ttys file appeared in Version 6 AT&T UNIX. BSD
March 9, 2014 BSD

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