1. Because they are small
2. Because they are used.
*YOU* (as an end user) use zsh, which is fine, but many parts of the system *require* bash to be around
If you have a problem on your system and ask a friend to help out, and he/she needs to dig, he/she will most likely start their fav shell first. zsh is a fine shell, but others may prefer bash or tcsh. (I belong to the ones that us tcsh as my base shell, but *not* for scripting, for which I use sh (any POSIX compliant) or perl)
3. Because you might not be the only user
If you add your friend/child/partner to your system, they might prefer one of the alternatives, and bash is - like it or not - the de-facto default shell for users on Linux. New users expect that.
Look in /etc/shells to see that you have probably more than 3:
/bin/ash /bin/bash /bin/csh /bin/dash /bin/false /bin/ksh /bin/ksh93 /bin/mksh /bin/pdksh /bin/sh /bin/tcsh /bin/true /bin/zsh /usr/bin/csh /usr/bin/dash /usr/bin/ksh /usr/bin/ksh93 /usr/bin/mksh /usr/bin/passwd /usr/bin/pdksh /usr/bin/bash /usr/bin/tcsh /usr/bin/zsh /usr/bin/fish I wasn't saying that bash shouldn't be installed if I use something else. I do know that bash is the default shell and it would break a lot of
On Sat, 22 Jun 2019 at 10:52, H.Merijn Brand