Must add interface for modules (input, login, output, framebuffer, tty)
Write a fbgetty_vsprintf() to parse login prompt
Use of readline
Config file

add command in form /command (like irc) on login prompt ...
 /set name=value
 /echo name
 /restart
 /refresh

add completion on login prompt
prompt> [TAB]
Help: type your login here
 could be in: root meuh anonymous top
prompt> anony [TAB]
prompt> anonymous

The completion could be in a list (file login.list)

set $HOME to fbgetty config directory

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login.list

# comment

*    "HELP: type your login here\n could be in: root meuh anonymous top" # * is the none completion
root "What did you want"
lch
yann_droneaud
coucou
meuh
anonymous

# end of file
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config files ...

/etc/fbgetty.d/ or /etc/fbgetty/*
   global.cfg or config
   tty0.cfg or tty0
   tty2.cfg 
   login.list or login
   .inputrc (for readline) 

----------------------------------
Configuration file:
*.cfg

# a config file
# a comment

fb_file = /dev/fb0
login_command = /sbin/login.out
prompt = "%n login:"

inputrc = \ 
 bell style visible \
 meta convert off 

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