s/// can do the job: use .{1,$x} to get the first 1 to $x characters, discarding any after $x, then pack "A$x" to space-pad to $x. 
#!perl
use strict;
my $fixlen = 5;
my @words = qw( s so som some somew somewo somewor someword somewords)
+;
foreach my $word (@words) {
  $word =~ s/^(.{1,$fixlen}).*$/pack "A$fixlen", $1/e;
  print ">$word<\n";
}
__END__
>s    <
>so   <
>som  <
>some <
>somew<
>somew<
>somew<
>somew<
>somew<

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In reply to Re: fixed length string by keszler
in thread fixed length string by shilpam

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