sub pad
{
   my $str = shift;
   my $maxlen = shift;
   my $char = shift || " ";

   return $char x ($maxlen - length($str)) . $str;
}

print pad("Foo Bar", 30, "x"); # prints 'xxxxxxxxxxxxxxxxxxxxxxxFoo Ba
+r'
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I wonder if this might be a good time to use Perl's bizarre pass-by-reference semantics?

sub pad {
  my $char = pop;
  my $max = pop;
  
  $char = " " unless defined $char;
  $_[0] .= $char x ($max - length $_[0]);
}
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Now:

    pad($v, 30, 'x');    # $v is now 30 characters long
    print $v;
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sprintf("%10d", 1234) will give you "......1234" (those '.' are spaces, really, but PM formatting weirds it out).

sprintf("%010d", 1234) will give you "0000001234"

If you want x's instead, then try this (assuming you only have numerics and no strings)

$text = sprintf("%10d", $number);
$text =~ s/\s/x/g;
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#!perl -w

use strict;

my $template = ' ' x 60;

sub insert {
  my (undef, $field, $position) = @_;
  substr($_[0], $position, length($field)) = $field;
}

my $record = $template;
insert($record, 'abc', 0);
insert($record, 'ghi', 6);

print "[$record]\n";
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