I have reduced my problem to the following: I have two scripts, A.ksh & B.ksh. Each is identical and they look like:

#!/usr/bin/ksh
Count=0
Limit=30
while [ $Count -lt $Limit ] ;
do
   Count=$(($Count + 1))
   sleep 1
   echo $0 has Slept for \[$Count\] Seconds so Far...
done

[download]

My goal is to write a Perl script that executes them in parallel and prints their output. This is what I have:

#!/usr/bin/perl
use strict;
use warnings;

my @Types = ('A', 'B');

my %ScriptName;
my %IsFinished;
my %ProcesseHandle;
foreach my $Type (@Types)
   {
   $ScriptName{$Type} = $Type . '.ksh';
   $IsFinished{$Type} = 0;
   if(!open($ProcesseHandle{$Type}, "$ScriptName{$Type}|"))
      {
      WarnLog("Unable to run Script:[$ScriptName{$Type}]:\n$^E:\n$!:\n
+Error Number $?:$@ ");
      }

   }

while(!$IsFinished{'A'} or !$IsFinished{'B'})
   {
   my %Line;
   foreach my $Type (@Types)
      {
      if(!$IsFinished{$Type})
         {
         $Line{$Type} = <$ProcesseHandle{$Type}>;
         if(!defined($Line{$Type}))
            {
            $IsFinished{$Type} = 1;
            }
         print("\[$Type\]\[$Line{$Type}\]\n");
         }
      }
   }

[download]

And this is what I get: 

[A][GLOB(0x2ae38)]
Use of uninitialized value in concatenation (.) or string at HashPipe.
+pl line 33.
[B][]
[A][GLOB(0x2ae38)]
Use of uninitialized value in concatenation (.) or string at HashPipe.
+pl line 33.
[A][]

[download]

And of course it hangs there. Obviously $Line{$Type} = <$ProcesseHandle{$Type}>; isn't doing what I expect. Why?

Also is there a better way to do while(!$IsFinished{'A'} or !$IsFinished{'B'}) so I don't have to hardcode the keys?

Thanks!

In reply to Hash Pipe Problem by NateTut

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