What does cdup () do in FTP?

Perl programs have this filehandle that is automatically opened:

Perl has a 'goto' command.

How can you install a module?

What's the preferable mode of executing one CGI script?

How do I call subroutines in Perl?

Which Perl command will print the output, 175?

Output of the Perl program? use strict; my @x = ('Red', 'Blue', 'Black'); print `@x = ` . '@x\n'; my ($Mary, $Lisa, $Lara)= @x; print '$Mary $Lisa $Lara\n'; my ($here, $there)= @x; print '$here $there\n'; my ($this) = @x; print '$this\n'; my $this = @x; print '$this\n'; my ($a, $b, $c, $d, $e)= ('a', 'b', 'c', 'd', 'e'); print '[$a] [$b] [$c] [$d] [$e]\n'; ($a, $b, $c, $d, $e)= @x; print '[$a] [$b] [$c] [$d] [$e]\n'; my $var_a = 'Monday'; my $var_b = 'Friday'; ($var_a, $var_b)= ($var_b, $var_a); print '$var_a $var_b\n';

Which is the correct syntax of a subroutine that makes a positional parameter, say 'right', optional? (Assume the name of the subroutine as example, and left and right as the positional parameters.)

Which value is returned by the Perl eof function if the next read on FILEHANDLE returns the end of file or if the FILEHANDLE is not open?

Which operator is NOT used in Perl?