Hello geofflh, and welcome to the Monastery!

Here’s another syntax variation you may find useful: including * in the format string of a call to printf (or sprintf):

use strict;
use warnings;

my $w   = 7;
my $str = "abc";
printf ">%*s<\n", $w, $str;
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Output:

17:34 >perl 1790_SoPW.pl
>    abc<

17:34 >
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— the * is replaced by the contents of the next variable in the following list, in this case $w, so the statement is equivalent to printf ">%7s<\n, $str.

Hope that helps,