foreach (@cfg_content)
{       
...
        my $subframe=   $file_frame_main        ->Frame(-relief =>'groove',-borderwidth =>2)->pack(-padx => 5, -pady => 1,-side => 'top',-anchor=>'nw',-fill=>'x'); #Frame for file info
        my $sub_header=         $subframe               ->Frame()->pack(-side=>'top',-fill=>'x');
        my $sub_read_sect=      $subframe               ->Frame()->pack(-side=>'top',-fill=>'x');
        $sub_header->Label(-text => "$gui_text ($abbr)\[$framecounter\]")->pack(-side =>'top',-fill=>'x');
        my $sub_read_sect_entry=$sub_read_sect->Entry()->pack(-anchor=>'w',-side=>'left');
        $sub_read_sect->Button(-text => "for reading",-command => 
                sub {
                        @sub_write_sect_entry[$framecounter]->delete(0,length(@sub_write_sect_entry[$framecounter]->get()));
                        print "$framecounter"
                } )->pack(-anchor=>'e',-side=>'right',-fill=>'x');
        $framecounter+=1;
...
}

#!/usr/bin/perl
use strict;
use warnings;

use Tk;

my $mw	= MainWindow->new();

foreach my $index (1..6){
	my $frame	= $mw->Frame()->pack();

	$frame->Button(
		-text => "Button $index",
		-command => sub{
			print "Frame $index\n";
		}
	)->pack();
}

Tk::MainLoop();