PerlingTheUK,
Nothing in your code indicates why a string '0' would show up as unprintable/space. You however have way over complicated things: 
#!/usr/bin/perl
use strict;
use warnings;

while ( <DATA> ) {
    chomp;
    print format_time( split " " , $_ ), "\n";
}
sub format_time {
    return sprintf("%.2d:%.2d:%.2d", @_)
}
__DATA__
9 12 54
23 8 7

[download]

Cheers - L~R

In reply to Re: scalar number with preceding 0. by Limbic~Region
in thread scalar number with preceding 0. by PerlingTheUK

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