$shopt -s checkwinsize on cmdhist on complete_fullquote on expand_aliases on extglob on extquote on force_fignore on histappend on interactive_comments on progcomp on promptvars on sourcepath on $shopt -s cdspell $shopt -s cdspell on checkwinsize on cmdhist on complete_fullquote on expand_aliases on extglob on extquote on force_fignore on histappend on interactive_comments on progcomp on promptvars on sourcepath on $shopt -s gnu bash: shopt: gnu: invalid shell option name $cd /etc/ap apache2/ apm/ apparmor/ apparmor.d/ apport/ apt/ $cd /etc/apache3 /etc/apache2 $pwd /etc/apache2 $ http://www.gnu.org/software/bash/manual/html_node/The-Shopt-Builtin.html