Perl5 リファレンス

       print FILEHANDLE LIST

       print LIST

       print   Prints a string or a list of strings.  Returns
               true if successful.  FILEHANDLE may be a scalar
               variable name, in which case the variable contains
               the name of or a reference to the filehandle, thus
               introducing one level of indirection.  (NOTE: If
               FILEHANDLE is a variable and the next token is a
               term, it may be misinterpreted as an operator
               unless you interpose a `+' or put parentheses
               around the arguments.)  If FILEHANDLE is omitted,
               prints by default to standard output (or to the
               last selected output channel--see the select entry
               elsewhere in this document).  If LIST is also
               omitted, prints `$_' to the currently selected
               output channel.  To set the default output channel
               to something other than STDOUT use the select
               operation.  The current value of `$,' (if any) is
               printed between each LIST item.  The current value
               of `$\' (if any) is printed after the entire LIST
               has been printed.  Because print takes a LIST,
               anything in the LIST is evaluated in list context,
               and any subroutine that you call will have one or
               more of its expressions evaluated in list context.
               Also be careful not to follow the print keyword
               with a left parenthesis unless you want the
               corresponding right parenthesis to terminate the
               arguments to the print--interpose a `+' or put
               parentheses around all the arguments.

               Note that if you're storing FILEHANDLES in an
               array or other expression, you will have to use a
               block returning its value instead:

                   print { $files[$i] } "stuff\n";
                   print { $OK ? STDOUT : STDERR } "stuff\n";