##609823.pl
#! perl -slw
use strict;

my $count;
while( 1 ) {
    print "Iteration: ", ++$count;
    system 'perl 609823-1.pl';
    system 'perl 609823-2.pl';
}



## 609823-1.pl
#! perl -slw
use strict;

my $count = int rand 100;
open OUT, '>', 'output.txt' or die $!;
print OUT 'A line of junk' for 1 .. $count;
close OUT;

printf "Wrote $count lines \t";


## 609823-2.pl
#! perl -slw
use strict;

open IN, '<', 'output.txt' or die $!;
my @lines = <IN>;
printf "Read %d lines \t", scalar @lines;
close IN;
unlink 'output.txt';

## Produces
c:\test>609823
Iteration: 1
Wrote 72 lines  Read 72 lines   Iteration: 2
Wrote 19 lines  Read 19 lines   Iteration: 3
Wrote 97 lines  Read 97 lines   Iteration: 4
Wrote 58 lines  Read 58 lines   Iteration: 5
Wrote 94 lines  Read 94 lines   Iteration: 6
...