If your text is delimited (commas, tabs, pipe,...) I would use Text::CSV_XS. It will handle about any delimiter you can throw at it.
Code Example: 

use strict;
use warnings;
use Text::CSV_XS;


my $csv = Text::CSV_XS->new({ sep_char => '|' });
foreach my $line (<DATA>) {
    my $status = $csv->parse($line);
    if (!$status) {
        print $csv->error_input() . "\n";
        next;
    }
    my @cols = $csv->fields();
    print join(' # ',@cols);
    print "\n";
}

__DATA__
foo|bar|baz
aaa|bbb|ccc
ddd|eee|fff

[download]

If it's some kind of fixed length look at using unpack. unpack may take some learning but it offers great flexibility and IMO much cleaner code.
Code Example: 

use strict;
use warnings;

foreach my $line (<DATA>) {
    my @cols = unpack("a3a3a3",$line);
    print join(' # ',@cols);
    print "\n";
}

__DATA__
foobarbaz
aaabbbccc
dddeeefff

[download]

Now that you have an array just take a slice of the columns you want. 

    my @rtn = @cols[0,2];   #Grab the 1st and 3rd column
    print join(' # ',@rtn);
    print "\n";

[download]

As other have pointed out, you should help us help you.

UPDATE: Added code examples

grep
XP matters not. Look at me. Judge me by my XP, do you?

In reply to Re: Reading selected columns from text file by grep
in thread Reading selected columns from text file by beginr

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