Интерактивная система просмотра системных руководств (man-ов)
add-shell (8)
>> add-shell (8) ( Linux man: Команды системного администрирования )
NAME
add-shell - add shells to the list of valid login shells
SYNOPSIS
add-shellshellname
[shellname...]
DESCRIPTION
add-shell
copy /etc/shells to /etc/shells.tmp, add the given shells to
this file if they are not already present, and copy this temporary file
back to /etc/shells.
The shells must be provided by their full pathnames.