"install" and "envsubst" shell commands missing from OpenWrt

I search the install command and the envsubst command for adding them to OpenWrt !
Can anyone give a clue or advice about these GNU/Linux command, which look to still missing from OpenWrt ?

The shell is already there:

root@OpenWrt:/etc/config# sh

BusyBox v1.30.1 () built-in shell (ash)

root@OpenWrt:/etc/config#

Is it something else you're looking for?

yes...

I have also installed bash and coreutils.
I want to have more commands ; these ones for now ;

Ah, I see now - apologies.

Where you would often compile and install a package directly on most Linux distributions the OpenWRT way is to use cross compilation to build a package that opkg installs, rather than install at the end of a compile. Would that approach work for you?

EDIT: So those utilities would be used in the compilation / build environment, typically a "full" Linux system.

gettext-full is in git: https://git.openwrt.org/?p=openwrt/openwrt.git;a=tree;f=package/libs/gettext-full

I don't dabble at that level much, but I think that means you can install the package to your own build environment with (IIRC) scripts/install.sh, and select it in make menuconfig to build it as an OpenWRT package. You could then add it to the image you flash to the device - or copy package to install with opkg.

You may be wondering why it isn't built already. I think the answer is that there are lots of packages that would hardly ever get installed, so it reduces maintenance / CI overhead. The downside is that it may be broken when you try to build it.

EDIT: Just realised that is to build the library. You may be able to adjust it to build the installable utilities as well.

install is listed as a capability of busybox: https://busybox.net/downloads/BusyBox.html.

I thought there was something like busybox-full that opkg could install, but not finding it right now. You may be able to adjust the package build to add that applet.