Re^2: Progress Bar in Perl script

I've been away from Perl for too long... I hope I'm not misunderstanding some fundamental principal here...

When I run this code from the command line, what I don't understand is how the "spinner" is printing over itself to the screen.
I understand that @sail is being interated through by incrementing $sail, but what part of this code is making the contents of @sail print on top of each other, i.e. making the "spinner" effect?

   my @sails = map { "\b$_" } qw{- \ | /};
    my $sail = 0;

    {
        local $| = 1;

        print q{Running:  };

        for (0 .. 1000) {
            system $cmd and die qq{'$cmd' failed! $? : $!};

            print $sails[$sail++ % @sails] if not $_ % $skip;
        }
    }
[download]

Any help here? What am I overlooking?

Comment on Re^2: Progress Bar in Perl script Download Code

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Re^3: Progress Bar in Perl script by kcott (Archbishop) on Mar 13, 2013 at 14:46 UTC
Each of the sails is created by prepending a "`\b`" to the spinner character: `my @sails = map { "\b$_" } qw{- \ \| /};` [download] "`\b`" is a backspace character; so, when each sail is printed, it deletes the previous one. In the initial state, "Running:" is followed by two spaces (`print q{Running: };`); the second space is overwritten by the first sail. "`\b`", and other special characters, are listed in perlop: Quote and Quote-like Operators. -- Ken	[reply] [d/l] [select]
Re^4: Progress Bar in Perl script by regexes (Hermit) on Mar 13, 2013 at 15:17 UTC
D'oh! Thanks! I knew I was overlooking something...	[reply]