Interesting, thank you Almut.

If you have time & inclination, I've one final line of enquiry: 

use strict;
use warnings;
use threads;

my $str = 'x' x 32_000_000;

sub fork_wait {
    my $pid = fork;
    if ($pid) {
        wait;
    }
    else {
        substr( $str, $_, 1 ) &= ~ ' ' for 0 .. length( $str ) -1;
        exit 0;
    }
}

sub create_thread_join {
    threads->create( sub {
        substr( $str, $_, 1 ) &= ~ ' ' for 0 .. length( $str ) -1;
    } )->join;
}

use Benchmark qw( cmpthese );

cmpthese - 3,
  {
    Forks   => \&fork_wait,
    Threads => \&create_thread_join,
  };

[download]

In reply to Re^7: while reading a file, transfer the same data to two different processes. by BrowserUk
in thread while reading a file, transfer the same data to two different processes. by avanta

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