glob EXPR
       glob    In list context, returns a (possibly empty) list of filename
               expansions on the value of EXPR such as the standard Unix shell
               /bin/csh would do. In scalar context, glob iterates through
               such filename expansions, returning undef when the list is
               exhausted. This is the internal function implementing the
               "<*.c>" operator, but you can use it directly. If EXPR is omit-
               ted, $_ is used.  The "<*.c>" operator is discussed in more
               detail in "I/O Operators" in perlop.