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GETTYTAB(5)               FreeBSD File Formats Manual              GETTYTAB(5)

     gettytab - terminal configuration data base


     The gettytab file is a simplified version of the termcap(5) data base
     used to describe terminal lines.  The initial terminal login process
     getty(8) accesses the gettytab file each time it starts, allowing simpler
     reconfiguration of terminal characteristics.  Each entry in the data base
     is used to describe one class of terminals.

     There is a default terminal class, default, that is used to set global
     defaults for all other classes.  (That is, the default entry is read,
     then the entry for the class required is used to override particular

     Refer to termcap(5) for a description of the file layout.  The default
     column below lists defaults obtained if there is no entry in the table
     obtained, nor one in the special default table.

     Name    Type    Default           Description

     ac      str     unused            expect-send chat script for modem
     al      str     unused            user to auto-login instead of prompting
     ap      bool    false             terminal uses any parity
     bk      str     0377              alternate end of line character (input
     c0      num     unused            tty control flags to write messages
     c1      num     unused            tty control flags to read login name
     c2      num     unused            tty control flags to leave terminal as
     ce      bool    false             use crt erase algorithm
     ck      bool    false             use crt kill algorithm
     cl      str     NULL Ta screen clear sequence
     co      bool    false             console - add `\n' after login prompt
     ct      num     10                chat timeout for ac and ic scripts
     dc      num     0                 chat debug bitmask
     de      num     0                 delay secs and flush input before
                                       writing first prompt
     df      str     %+                the strftime(3) format used for %d in
                                       the banner message
     ds      str     `^Y' Ta delayed suspend character
     dx      bool    false             set DECCTLQ
     ec      bool    false             leave echo OFF
     ep      bool    false             terminal uses even parity
     er      str     `^?' Ta erase character
     et      str     `^D' Ta end of text (EOF) character
     ev      str     NULL Ta initial environment
     f0      num     unused            tty mode flags to write messages
     f1      num     unused            tty mode flags to read login name
     f2      num     unused            tty mode flags to leave terminal as
     fl      str     `^O' Ta output flush character
     hc      bool    false             do NOT hangup line on last close
     he      str     NULL Ta hostname editing string
     hn      str     hostname          hostname
     ht      bool    false             terminal has real tabs
     hw      bool    false             do cts/rts hardware flow control
     i0      num     unused            tty input flags to write messages
     i1      num     unused            tty input flags to read login name
     i2      num     unused            tty input flags to leave terminal as
     ic      str     unused            expect-send chat script for modem
     if      str     unused            display named file before prompt, like
     ig      bool    false             ignore garbage characters in login name
     im      str     NULL Ta initial (banner) message
     in      str     `^C' Ta interrupt character
     is      num     unused            input speed
     kl      str     `^U' Ta kill character
     l0      num     unused            tty local flags to write messages
     l1      num     unused            tty local flags to read login name
     l2      num     unused            tty local flags to leave terminal as
     lm      str     login:            login prompt
     ln      str     `^V' Ta ``literal next'' character
     lo      str     /usr/bin/login Ta program to exec when name obtained
     mb      bool    false             do flow control based on carrier
     nc      bool    false             terminal does not supply carrier (set
     nl      bool    false             terminal has (or might have) a newline
     np      bool    false             terminal uses no parity (i.e. 8-bit
     nx      str     default           next table (for auto speed selection)
     o0      num     unused            tty output flags to write messages
     o1      num     unused            tty output flags to read login name
     o2      num     unused            tty output flags to leave terminal as
     op      bool    false             terminal uses odd parity
     os      num     unused            output speed
     pc      str     `\0' Ta pad character
     pe      bool    false             use printer (hard copy) erase algorithm
     pf      num     0                 delay between first prompt and
                                       following flush (seconds)
     pl      bool    false             start PPP login program unconditionally
                                       if pp is specified
     pp      str     unused            PPP login program
     ps      bool    false             line connected to a MICOM port selector
     qu      str     `^\' Ta quit character
     rp      str     `^R' Ta line retype character
     rt      num     unused            ring timeout when using ac
     rw      bool    false             do NOT use raw for input, use cbreak
     sp      num     unused            line speed (input and output)
     su      str     `^Z' Ta suspend character
     tc      str     none              table continuation
     to      num     0                 timeout (seconds)
     tt      str     NULL Ta terminal type (for environment)
     ub      bool    false             do unbuffered output (of prompts etc)
     we      str     `^W' Ta word erase character
     xc      bool    false             do NOT echo control chars as `^X'
     xf      str     `^S'              XOFF (stop output) character
     xn      str     `^Q'              XON (start output) character
     Lo      str     C                 the locale name used for %d in the
                                       banner message

     The following capabilities are no longer supported by getty(8):

     bd      num     0                 backspace delay
     cb      bool    false             use crt backspace mode
     cd      num     0                 carriage-return delay
     fd      num     0                 form-feed (vertical motion) delay
     lc      bool    false             terminal has lower case
     nd      num     0                 newline (line-feed) delay
     uc      bool    false             terminal is known upper case only

     If no line speed is specified, speed will not be altered from that which
     prevails when getty is entered.  Specifying an input or output speed will
     override line speed for stated direction only.

     Terminal modes to be used for the output of the message, for input of the
     login name, and to leave the terminal set as upon completion, are derived
     from the boolean flags specified.  If the derivation should prove
     inadequate, any (or all) of these three may be overridden with one of the
     c0, c1, c2, i0, i1, i2, l0, l1, l2, o0, o1, or o2 numeric specifications,
     which can be used to specify (usually in octal, with a leading '0') the
     exact values of the flags.  These flags correspond to the termios
     c_cflag, c_iflag, c_lflag, and c_oflag fields, respectively.  Each these
     sets must be completely specified to be effective.  The f0, f1, and f2
     are excepted for backwards compatibility with a previous incarnation of
     the TTY sub-system.  In these flags the bottom 16 bits of the (32 bits)
     value contain the sgttyb sg_flags field, while the top 16 bits represent
     the local mode word.

     Should getty(8) receive a null character (presumed to indicate a line
     break) it will restart using the table indicated by the nx entry.  If
     there is none, it will re-use its original table.

     Delays are specified in milliseconds, the nearest possible delay
     available in the tty driver will be used.  Should greater certainty be
     desired, delays with values 0, 1, 2, and 3 are interpreted as choosing
     that particular delay algorithm from the driver.

     The cl screen clear string may be preceded by a (decimal) number of
     milliseconds of delay required (a la termcap).  This delay is simulated
     by repeated use of the pad character pc.

     The initial message, login message, and initial file; im, lm and if may
     include any of the following character sequences, which expand to
     information about the environment in which getty(8) is running.

           %d               The current date and time formatted according to
                            the Lo and df strings.

           %h               The hostname of the machine, which is normally
                            obtained from the system using gethostname(3), but
                            may also be overridden by the hn table entry.  In
                            either case it may be edited with the he string.
                            A '@' in the he string causes one character from
                            the real hostname to be copied to the final
                            hostname.  A '#' in the he string causes the next
                            character of the real hostname to be skipped.
                            Each character that is neither '@' nor '#' is
                            copied into the final hostname.  Surplus '@' and
                            '#' characters are ignored.

           %t               The tty name.

           %m, %r, %s, %v   The type of machine, release of the operating
                            system, name of the operating system, and version
                            of the kernel, respectively, as returned by

           %%               A ``%'' character.

     When getty execs the login process, given in the lo string (usually
     ``/usr/bin/login''), it will have set the environment to include the
     terminal type, as indicated by the tt string (if it exists).  The ev
     string, can be used to enter additional data into the environment.  It is
     a list of comma separated strings, each of which will presumably be of
     the form name=value.

     If a non-zero timeout is specified, with to, then getty will exit within
     the indicated number of seconds, either having received a login name and
     passed control to login(1), or having received an alarm signal, and
     exited.  This may be useful to hangup dial in lines.

     Output from getty(8) is even parity unless op or np is specified.  The op
     string may be specified with ap to allow any parity on input, but
     generate odd parity output.  Note: this only applies while getty is being
     run, terminal driver limitations prevent a more complete implementation.
     The getty(8) utility does not check parity of input characters in RAW

     If a pp string is specified and a PPP link bring-up sequence is
     recognized, getty will invoke the program referenced by the pp option.
     This can be used to handle incoming PPP calls.  If the pl option is true
     as well, getty(8) will skip the user name prompt and the PPP detection
     phase, and will invoke the program specified by pp instantly.

     Getty provides some basic intelligent modem handling by providing a chat
     script feature available via two capabilities:

           ic        Chat script to initialize modem.
           ac        Chat script to answer a call.

     A chat script is a set of expect/send string pairs.  When a chat string
     starts, getty will wait for the first string, and if it finds it, will
     send the second, and so on.  Strings specified are separated by one or
     more tabs or spaces.  Strings may contain standard ASCII characters and
     special 'escapes', which consist of a backslash character followed by one
     or more characters which are interpreted as follows:

           \a        bell character.
           \b        backspace.
           \n        newline.
           \e        escape.
           \f        formfeed.
           \p        half-second pause.
           \r        carriage return.
           \S, \s    space character.
           \t        tab.
           \xNN      hexadecimal byte value.
           \0NNN     octal byte value.

     Note that the `\p' sequence is only valid for send strings and causes a
     half-second pause between sending the previous and next characters.
     Hexadecimal values are, at most, 2 hex digits long, and octal values are
     a maximum of 3 octal digits.

     The ic chat sequence is used to initialize a modem or similar device.  A
     typical example of an init chat script for a modem with a hayes
     compatible command set might look like this:

           :ic="" ATE0Q0V1\r OK\r ATS0=0\r OK\r:

     This script waits for nothing (which always succeeds), sends a sequence
     to ensure that the modem is in the correct mode (suppress command echo,
     send responses in verbose mode), and then disables auto-answer.  It waits
     for an "OK" response before it terminates.  The init sequence is used to
     check modem responses to ensure that the modem is functioning correctly.
     If the init script fails to complete, getty considers this to be fatal,
     and results in an error logged via syslogd(8), and exiting.

     Similarly, an answer chat script is used to manually answer the phone in
     response to (usually) a "RING".  When run with an answer script, getty
     opens the port in non-blocking mode, clears any extraneous input and
     waits for data on the port.  As soon as any data is available, the answer
     chat script is started and scanned for a string, and responds according
     to the answer chat script.  With a hayes compatible modem, this would
     normally look something like:

           :ac=RING\r ATA\r CONNECT:

     This causes the modem to answer the call via the "ATA" command, then
     scans input for a "CONNECT" string.  If this is received before a ct
     timeout, then a normal login sequence commences.

     The ct capability specifies a timeout for all send and expect strings.
     This timeout is set individually for each expect wait and send string and
     must be at least as long as the time it takes for a connection to be
     established between a remote and local modem (usually around 10 seconds).

     In most situations, you will want to flush any additional input after the
     connection has been detected, and the de capability may be used to do
     that, as well as delay for a short time after the connection has been
     established during which all of the connection data has been sent by the

     login(1), gethostname(3), uname(3), termcap(5), getty(8), telnetd(8)

     The gettytab file format appeared in 4.2BSD.

     The special characters (erase, kill, etc.) are reset to system defaults
     by login(1).  In all cases, '#' or '^H' typed in a login name will be
     treated as an erase character, and '@' will be treated as a kill

     The delay stuff is a real crock.  Apart form its general lack of
     flexibility, some of the delay algorithms are not implemented.  The
     terminal driver should support sane delay settings.

     The he capability is stupid.

     The termcap(5) format is horrid, something more rational should have been

FreeBSD 11.0-PRERELEASE         April 19, 1994         FreeBSD 11.0-PRERELEASE


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