dog diz exit 0 exit 0 dog diz exit 0 exit 0 exit 1 exit 1 y exit 0 exit 1 exit 0 exit 1 12 ab bc de example com /usr/local/bin fish a b c 1...2...3 abc abc x zan \cg a axxb Axxb ok? dog 2:34:56 2 34 56 papa pa murmur mur 2 2 4 2 6 2 0xBadC0de blue was my favorite 1st 2nd last spaces_to_underscores 0 3.14 5 right left $ put a here aabb invalid expression error invalid argument error missing argument returns 0 no regexp invert match no glob invert match 1 3