Hi again Monks,

I have duplicated the issue. I just simply wrapped the STDIN check in a function. When I run this very simple script through the pipe, can_read() doesn't detect anything on STDIN. When I run it through the debugger, it works fine. When I uncomment the print statement in checkPipe, it triggers something and works fine without the debugger! What am I possibly doing wrong here? I am losing my sanity! Could it possibly be the timeout as Bliako stated? I tried changing it, but it doesn't seem to change anything. 

 
#
# TEST RUN #
#
# perl test2.pl | perl  test2.pl
## PRINTS NOTHING !!!

[download]
# perl test2.pl | perl -d  test2.pl

reading from pipe data
.------------------------------.
|            Basket            |
+----+-----------------+-------+
| Id | Name            | Price |
+----+-----------------+-------+
|  1 | Dummy product 1 |  24.4 |
|  2 | Dummy product 2 |  21.2 |
|  3 | Dummy product 3 |  12.3 |
+----+-----------------+-------+
|    | Total           |  57.9 |
'----+-----------------+-------'

[download]
## test2.pl
#
#!/usr/bin/perl5.26.1
use strict;

use Text::ASCIITable;
use IO::Select;
use strict;
use warnings;

$|=1; 

checkPipe();

sub checkPipe {

    #print "checking pipe\n";  #<==== UNCOMMENT IT WORKS!!
    my $s = IO::Select->new();
    $s->add(\*STDIN);

    if ($s->can_read(.5)) {
        print STDOUT "reading from pipe data\n";
        dumpTable();
        
    }


}

sub dumpTable {
  my $t = Text::ASCIITable->new({ headingText => 'Basket' });
  
  $t->setCols('Id','Name','Price');
  $t->addRow(1,'Dummy product 1',24.4);
  $t->addRow(2,'Dummy product 2',21.2);
  $t->addRow(3,'Dummy product 3',12.3);
  $t->addRowLine();
  $t->addRow('','Total',57.9);
 
  print STDOUT $t ."\n";
}

[download]

In reply to Re: IO::Select woes by Anonymous Monk
in thread IO::Select woes by Anonymous Monk

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