I tried: 
#!/usr/local/bin/perl

use strict;
use warnings;

use IO::Handle;
use IO::Select;

my $handle;
my $pid;
if (!defined($pid = open($handle, "|-"))) {
    die "Fork failed: ".$!;
}
elsif ($pid == 0) {
    # Child
    sleep(5);
    exit 0;
}
else {
    # Parent
    $handle->autoflush(1);
    my $selector = IO::Select->new($handle);
    my $i = 0;
    do {
        if ($selector->can_write(0)) {
            print $handle "ABC\n";
            print "PIPE write ".++$i."\n";
        }
        else {
            print "PIPE cannot write\n";
        }
    } while (1);
}

[download]
but only one pipe write is successful and then the can_write check fails every time. Can you be more specific please?

FYI, I am on Linux

In reply to Re^2: Non-blocking pipe write by Marcello
in thread Non-blocking pipe write by Marcello

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.