How to change the architecture of a Termux installation?

[groszdaniel]

I've switched from an OS ("ROM") with a 32-bit userland ("a64") to a fully 64-bit one. (The same question could come up when switching to a different phone.)

I made both a backup of the contents of /data/data/com.termux/files, and a full backup of the app and its data with NeoBackup before wiping the data partition; afterwards I restored the Termux app with NeoBackup, and I had the home directory, installed packages etc. all fully working, so the other backup was not even needed.

But the installed packages are still 32-bit. Is there a way to change the architecture of the installation (presumably involving reinstalling all packages) without doing a full reinstall of the app, or in particular preserving the list of installed packages, including which packages were installed automatically as dependencies?

(In my case, the reason I'd like to switch to 64-bit is to install deno to have better support for youtube in yt-dlp, which is only available in 64-bit.)

[robertkirkman]

But the installed packages are still 32-bit. Is there a way to change the architecture of the installation (presumably involving reinstalling all packages) without doing a full reinstall of the app, or in particular preserving the list of installed packages, including which packages were installed automatically as dependencies?

Unfortunately, I believe the most straightforward way to do this would be to use this command:

dpkg -l | grep ii | cut -d' ' -f3 > /storage/emulated/0/termux_packages_list.txt

and then uninstall Termux and clean install the 64-bit Termux again, then read the saved list and pass it to an apt install command to reinstall the packages.

I assume you'd want to make sure to omit nodejs from the list and install deno instead, but other than that, it should give you all the same packages you had (but 64-bit instead of 32-bit).

[robertkirkman]

If you need some commands to do this in full, I have checked these, which seem to work:

First, commands before uninstalling Termux:

termux-setup-storage
pkg upgrade # make sure the message 'Not upgrading' does not show at all
dpkg -l | grep ii | cut -d' ' -f3 > /storage/emulated/0/termux_packages_list.txt

next, uninstall Termux, then reinstall 64-bit Termux again, and use these commands:

termux-setup-storage
pkg upgrade
termux_packages_list=$(cat /storage/emulated/0/termux_packages_list.txt)
apt reinstall $termux_packages_list