It's not exactly
simple, but here's how to do it the old-fashioned way with
pipe,
sysread, and
syswrite. Note how the pipe protocol uses the number of bytes transferred in every message to detect its length:
use strict;
my @array = ();
pipe my $read, my $write or
die "Cannot open pipe";
for(1..3) {
defined(my $pid = fork) or die "Can't fork\n";
if($pid) {
next; # Parent: continue loop
}
# Child
pipe_send($write, "I'm process $$!");
exit 0;
}
# Parent
for(1..3) {
my $element = pipe_recv($read);
push @array, $element;
}
print "array = @array\n";
##################################################
sub pipe_send {
##################################################
my($fh, $message) = @_;
my $bytes = sprintf "0x%08x", length($message);
syswrite($fh, $bytes . $message);
}
##################################################
sub pipe_recv {
##################################################
my($fh) = @_;
die "Protocol corrupted" if
sysread($fh, my $bytes, 10) != 10;
$bytes = hex($bytes);
my $data = "";
while($bytes != 0) {
my $read = sysread($fh, my $chunk, $bytes);
last unless defined $read;
$bytes -= $read; $data .= $chunk;
}
return $data;
}
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