I was able to recreate the behavior in this script below. Note that an element of plist is getting cleared in each iteration. 
use strict;
use IPC::Open3;

my @plist = ("ABC","DEF","GHI");

print "plist Before ccmexec:\n============\n",join("\n",@plist),"\n===
+=========\n\n";

my $ccmexecResult;
foreach( @plist){
    $ccmexecResult = ccmexec_nodie("echo HelloWorld");
    
    print "ccmexec returned: $ccmexecResult\n";
    print "plist After ccmexec:\n============\n",join("\n",@plist),"\n
+============\n\n";
}

sub ccmexec_nodie {
    my $command = $_[0];
      
    my ($mystdin,$mystdout,$mystderr);
    my $pid = open3($mystdin,$mystdout,$mystderr,$command);
   
    my $myresult = "";
    while(<$mystdout>){
         $myresult = "$myresult$_";
    }
  
    return $myresult;
}

[download]
This produced the output: 
plist Before ccmexec:
============
ABC
DEF
GHI
============

ccmexec returned: HelloWorld


plist After ccmexec:
============

DEF
GHI
============

ccmexec returned: HelloWorld


plist After ccmexec:
============


GHI
============

ccmexec returned: HelloWorld


plist After ccmexec:
============



============

[download]

In reply to Re^2: Why are elements of my array getting deleted? by iKnowNothing
in thread Why are elements of my array getting deleted? by iKnowNothing

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