Hello.
First of all using the diamond operator (<>) is *not* non-blocking.
Also, using print means that you use buffers; the problem is not in the consumer, but in the producer.
See the following working examples:
#!/usr/bin/perl -w
# producer.pl

use strict;

while(1){
        syswrite(STDOUT,"Hello\n",length("Hello\n"));
        sleep(2);
}

[download]

#!/usr/bin/perl -w
# consumer.pl

use strict;

my $line;

while ($line = <STDIN>){
    print "$line";
}
=pod
my $line;
my $buf;

while (sysread(STDIN,$buf,1)){
    if ($buf =~ /\n|\r|\r\n/o){
        print "$line\n";
        $line = "";
    }else{
        $line.=$buf;
    }
}
=cut

[download]
Hope this helps ;-)
Dodge This!

In reply to Re: Read from a Linux pipe hangs. by Ultra
in thread Read from a Linux pipe hangs. by dmor4477

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