How to enable Linux to auto login at bootup

This howto show you howto get Linux to auto login in multi-user mode(non-GUI) at bootup.

Requirements

 * getty, or agetty; any getty that supports executing files (mingetty does not)
 * gcc: usually standard http://gcc.gnu.org
 * a boot disk or live cd is a good idea. If you make a mistake your computer may not boot up properly.

Steps
You may not boot up if this isn't done properly, and these steps may not be the same for your computer NOTE! If your computer does not boot up properly use your boot disk to replace the line in '/etc/inittab' to its original and read 'man getty'
 * 1) edit a file: for example 'autologinz.c', and add (zymos being the username)
 * #include &lt;unistd.h&gt;
 * int main { execlp( "login", "login", "-f", "zymos", 0); }
 * 1) Compile the file by executing this command:
 * gcc -o autologinz autologinz.c
 * 1) make sure autologinz is executable.  For help See: Howto to change file permissions in unix
 * 2) chmod 755 autologinz
 * 3) as root, perform the next steps:
 * 4) copy the program you just created to /usr/local/sbin
 * 5) cp autologinz /usr/local/sbin
 * 6) Read NOTE! below before proceeding!
 * 7) edit '/etc/inittab', and on line that looks similar to the following
 * c1:2345:respawn:/sbin/agetty 38400 tty1 linux
 * or
 * 1:2345:respawn:/sbin/mingetty tty1
 * 1) Replace that line with the following using the location of your executable
 * c1:2345:respawn:/sbin/agetty -n -l /usr/local/sbin/autologinz 38400 tty1
 * or
 * 1:2345:respawn:/sbin/agetty -n -l /usr/local/sbin/autologinz 38400 tty1
 * 1) reboot

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