\input texinfo   @c -*-texinfo-*-

@c %**start of header
@setfilename gates-of-tartaros.info
@settitle gates-of-tartaros
@afourpaper
@documentencoding UTF-8
@documentlanguage en
@finalout
@c %**end of header

@c --- start of do not touch ---
@set BIN /bin
@set SBIN /sbin
@set DEV /dev
@set ETC /etc
@set GOT got
@set SSH ssh
@c --- end of do not touch ---


@dircategory System
@direntry
* gates-of-tartaros: (gates-of-tartaros).   Extensible minimal TTY login manager with SSH support
@end direntry


@copying
Copyright @copyright{} 2013 Mattias Andrée

@quotation
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3 or
any later version published by the Free Software Foundation; with no
Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
Texts. A copy of the license is included in the section entitled
``GNU Free Documentation License''.
@end quotation
@end copying

@ifnottex
@node Top
@top gates-of-tartaros -- Extensible minimal TTY login manager with SSH support
@insertcopying
@end ifnottex

@titlepage
@title Gates of Tartaros
@subtitle Extensible minimal TTY login manager with SSH support
@author by Mattias Andrée (maandree)

@page
@vskip 0pt plus 1filll
@insertcopying
@c@page
@c@*@*
@c@center `'
@end titlepage

@contents



@menu
* Overview::                        Brief overview of Gates of Tartaros.
* Setting up::                      Setting up Gates of Tartaros.
* Extensibility::                   Configure and extend Gates of Tartaros.
* GNU Free Documentation License::  Copying and sharing this manual.
@end menu



@node Overview
@chapter Overview

Gates of Tartaros is a minimal, but extensible, replacement for
agetty written in GNU Bash. The be key feature of Gates of Tartaros
is that it lets you easily login to another computer with SSH.
@c Hence the name Gates of Tartaros, in MLP Kerberos gaurds the
@c gates of Tartaros (rather than Hades), the place where the
@c worst of pony kind gets after death, which in this analogy
@c is where you are before SSH:ing. When SSH:ing, Kerberos
@c (perhaps more specifically Heimdall) make sure you only get
@c in if you are authorised (getting in being getting out of
@c Tartaros.)

To login when Gates of Tartaros is running, just type your
username, but for an SSH session, type what you would type
as the argments for @command{@value{SSH}}. Normal patterns
for SSH logins include:

@itemize
@item @code{username@@hostname}
@item @code{username@@hostname port}
@end itemize



@node Setting up
@chapter Setting up

To set up your inittab to to use Gates of Tartaros instead
of @command{agetty}, in your inittab, use the command
@command{@value{SBIN}/@value{GOT}} with the first argument
being the tty it should open on (@code{tty1}, @code{tty2},
..., not @code{@value{DEV}/tty1}, @code{@value{DEV}/tty2},
...), followed by exports. For example:

@example
c1:345:respawn:@value{SBIN}/@value{GOT} tty1 TERM=linux
c2:345:respawn:@value{SBIN}/@value{GOT} tty2 TERM=linux
c3:345:respawn:@value{SBIN}/@value{GOT} tty3 TERM=linux
c4:345:respawn:@value{SBIN}/@value{GOT} tty4 TERM=linux
c5:345:respawn:@value{SBIN}/@value{GOT} tty5 TERM=linux
c6:345:respawn:@value{SBIN}/@value{GOT} tty6 TERM=linux
@end example



@node Extensibility
@chapter Extensibility

Extensions are loaded by Gates of Tartaros by sourcing
the file @file{@value{ETC}/@value{GOT}rc} if it exists.
@file{@value{ETC}/@value{GOT}rc} can change the behaviour
of Gates of Tartaros or source other files that does so.
The variable @code{tty} will be set from the beginning
to the TTY file, without @code{@value{DEV}/}, for example
@code{tty1}.

Gates of Tartaros as three functions is calls directly after
each other: @code{_display} for printing everying you see,
@code{_read} to accept username input and stores it in the
variable @code{user}, and then @code{_login} to start a
login. Password checking is handled by external programs
@command{@value{SSH}} and @command{login} that are used
doing the actual user login. You either redefine these
functions, or change the variables @code{display_function},
@code{read_function} or @code{login_function} to contain the
name of the functions you want to be called instead. The
latter option can be used to extend rather then replace the
predefined functions.

The file @file{@value{ETC}/os-release} will have been sources
before the extensions and @code{NAME} and @code{ANSI_COLOR}
will have fallback values. @code{NAME} is the name of
the operating system (distribution) and @code{ANSI_COLOR}
is its associated colour.



@node GNU Free Documentation License
@appendix GNU Free Documentation License
@include fdl.texinfo

@bye