% cat t0
#!/usr/bin/perl
use strict;
use warnings;

use IO::Select;
$|=1;
warn "pid $$ checking pipe\n";
my $s = IO::Select->new();
$s->add(\*STDIN);
if ($s->can_read(.5)) {
  warn "pid $$ can read\n";
  print "here is my table\n";
} else {
  warn "pid $$ cannot read\n";
}   
% ./t0 | ./t0
pid 24811 checking pipe
pid 24810 checking pipe
pid 24811 cannot read
pid 24810 cannot read
% echo "go" | ./t0 | ./t0
pid 26452 checking pipe
pid 26452 can read
pid 26453 checking pipe
pid 26453 can read
here is my table
%