Does anyone know how to modify mkinitcpio.conf in a script

[Linus No Beard]

I'm making an arch install script for myself and one of the things I need to do is modify mkinitcpio.conf to change the line

"HOOKS=(base udev autodetect modconf block filesystems keyboard fsck)" to

"HOOKS=(base udev autodetect modconf block encrypt lvm2 filesystems keyboard fsck)"

automatically how would I do this

[Master Disaster]

Adding data to the middle of a file like that isn't possible (at least AFAIK). Its much simpler to either delete the old file and replace it entirely or append a new version of the file over the old one.

 

1) Keep a copy of the modified file with your script and have it delete the existing file then download the modified one in its place.

 

2) something like this

sudo tee <<EOF > /etc/mkinitcpio.conf
***********full file content goes here*****************
EOF

which would overwrite the current contents of /etc/mkinitcpio.conf with whatever you put between the first EOF and the last EOF.

 

Edit - Now thatt I've said that, actually yes, it is possible to replace lines in files. Its used to apply patches to source code. Its called diff, no idea how to use it to create patches though, only ever used it to apply them.

 

Edit 2

4 hours ago, Linus No Beard said:

"HOOKS=(base udev autodetect modconf block filesystems keyboard fsck)"

Almost all of those hooks can be replaced with a single systemd hook, check out the Arch Wiki page on mkinitcpio for a nice comparison table.

[Nayr438]

You can use sed.

 

sed -i '/^HOOKS=/ s/filesystems/encrypt lvm2 &/g' /etc/mkinitcpio.conf

 

Edited March 26, 2022 by Nayr438
Use Insert instead of Replace. Cleanup, im bad at expressions.