Glob options

# Non-matching globs are removed 
# ('\*.foo' => '')
shopt -s nullglob   
# Non-matching globs throw errors
shopt -s failglob  
# Case insensitive globs
shopt -s nocaseglob 
# Wildcards match dotfiles 
# ("\*.sh" => ".foo.sh")
shopt -s dotglob    
# Allow \*\* for recursive matches 
# ('lib/\*\*/\*.rb' => 'lib/a/b/c.rb')
shopt -s globstar