Depending on what you mean by "input", be sure to put your separator in double quotes, not single quotes.

my @data = ("a", "b", "c");

say join "\t", @data;
say join '\t', @data;
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prints:

$ perl test.pl
a       b       c
a\tb\tc
$
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See perlop's section on quotes and quote-like operators.

Hi, The input is $char = <>: Then I use it like this: $out = "Field1$charField2$char....." Regards, Kepler

I'm not sure what the issue is, then. Take this snippet of code:

chomp(my $sep = <>);
say join $sep, @data;
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if I run this (with the above @data) and input a tab character, I do indeed get the output separated by tabs. Or do you want to be able to input the characters "\t" and have them interpreted as a tab, rather than a literal backslash followed by a literal lower-case t? In that case, you can use a regular expression to transform your separator:

chomp(my $sep = <>);
$sep =~ s/\\t/\t/g;
say join $sep, @data;
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use strict;
use warnings;

my $t = '\\t';
print "$t:\n";

my $evaled = eval "qq/$t/";
print "$evaled:\n"
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\t:
    :
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(perlmonks changes literal tab to several spaces, heh)

my %seps = (
  '\\t' => "\t",
  '\\n' => "\n",
   # etc
);

my $input = <>;
my $separator = $seps{$input};
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That works great... :) I was trying to substitute the "\" because of the \xhh character with hex. code hh. It's not working. Thanks. Kepler.

If you decided to use eval, you should really consider this:

# file eval.pl
use strict;
use warnings;

my $sep = shift @ARGV;
my $evaled = eval "qq/$sep/";
print "$evaled:\n"
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Now the user enters this:

perl eval.pl 'hehe/; print "Hello there!\n"; unlink "./eval.pl"; q/foo
+'
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Result:

Useless use of a constant ("hehe") in void context at (eval 1) line 1.
Hello there!
foo:
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And the eval.pl file is gone. So, yeah... as I said, eval is usually more trouble than it's worth. Maybe consider module Safe, which provides restricted eval, if you're dealing with users there (users are evil).