What follows is one from many different ways to get autologin.

== How ==
# Writing a wrapper, called autologin, around /bin/login and moving it in /usr/sbin/
# Editing /etc/inittab specifying the use of /usr/sbin/autologin instead of /bin/login

== Prerequisites ==
* A C compiler
* The '''''musl-dev''''' package which contains the C standard library

==== Example on how to assolve the prerequisites: ====
{{Cmd|# apk add --repository https://dl-cdn.alpinelinux.org/alpine/edge/testing tcc
# apk add musl-dev }}

== Writing the autologin.c program ==

Create a file; in this example called autologin.c
{{Cmd|# vi autologin.c }}

Write into it the following C program.

{{ cmd|&#35;include <unistd.h>

int main()
{
execlp( "login", "login", "-f", "root", 0);
}
}}

The only thing it does is a system call to execute the ''login'' binary (part of busybox) which will be searched in PATH.

As parameters are passed:
* '''-f''' flag which stands for "Do not authenticate (user already authenticated)"
* ''username'' in this example is ''root'' but if you created a new user, the user username can be used instead.

== Compiling the autologin.c program ==
If using tcc:
{{Cmd|&#35; tcc -o autologin autologin.c }}

Move the binary autologin to /usr/sbin
{{Cmd|&#35; mv autologin /usr/sbin/ }}

== Editing /etc/inittab ==

{{Cmd|&#35; sed -i 's@:respawn:/sbin/getty@:respawn:/sbin/getty -n -l /usr/sbin/autologin@g' /etc/inittab }}

The above command:
* replaces "'':respawn:/sbin/getty''" with "'':respawn:/sbin/getty -n -l /usr/sbin/autologin''"
* "'''@'''" is used as a delimiter
* The '''-i''' flag edits the file in-place
* The getty's '''-n''' flag do not prompt the user for a login name
* The getty's '''-l''' flag invokes a custom login instead of /bin/login; in our case it is set to invoke /usr/sbin/autologin

== Cleaning up ==
It is possible to remove the autologin.c file, the C compiler and the '''musl-dev''' package
{{Cmd|&#35; rm autologin.c
&#35; apk del tcc
&#35; apk del musl-dev}}

== Isn't this just reinventing the wheel? ==
Instead of going through the trouble of compiling something, wouldn't it be much easier to <code>apk add {{pkg|agetty}}</code> (from main) and use the {{key|-a}} (<small>{{key|--autologin}}</small>) option? &ndash;zcrayfish ([[User talk:zcrayfish|talk]]•[[Special:Contributions/zcrayfish|contribs]]•[[Special:EmailUser/zcrayfish|send email]]) 02:13, 11 September 2023 (UTC)