termux-packages/packages/termux-tools/chsh

#!/bin/sh

set -e -u

show_usage () {
	echo "usage: chsh [-s shell]"
	echo "Change the login shell."
}

set_shell () {
	if [ "$1" = login ]; then
		echo "login is not a valid shell"
		exit 1
	fi
	mkdir -p $HOME/.termux
	NEW_SHELL=$PREFIX/bin/$1
	if test -x $NEW_SHELL -a ! -d $NEW_SHELL; then
		ln -f -s $NEW_SHELL $HOME/.termux/shell
	else
		echo "$NEW_SHELL is not an executable file!"
	fi
}

O=`getopt -l help -- hs: "$@"`
eval set -- "$O"
while true; do
	case "$1" in
		-h|--help) show_usage; exit 0;;
		-s) set_shell $2; exit 0;;
		--)	shift; break;;
		*)	echo Error; show_usage; exit 1;;
	esac
done

DEFAULT_SHELL=bash
if [ ! -x $PREFIX/bin/$DEFAULT_SHELL ]; then DEFAULT_SHELL=ash; fi

echo Changing the login shell
echo Enter the new value, or press ENTER for the default
printf "        Login Shell [$DEFAULT_SHELL]: "
read shell

if [ -z "$shell" ]; then shell=$DEFAULT_SHELL; fi
set_shell $shell