I wasn't addressing your primary problem (although if you are using linux then try &2>1), but what appears to be a separate bug that will manifest itself when the current blocker bug is fixed.

Hi, I am new to open3 and perldoc is too vague to understand I am trying a simple perforce command to run in open3.Basically I want to capture both STDOUT and STDERR aswell.I have tried various ways but none of them seem to be working.I am hoping someone will comment.

foreach my $file (@changed_files)
{
    
#my $p4where_output=`p4 where $file > NUL: 2>&1`;#backticks option not
+ working,so commented out
#print "P4 where output:$p4where_output\n";

my $cmd = "p4 where $file";

local(*HIS_IN, *HIS_OUT, *HIS_ERR);

my $childpid = open3(*HIS_IN, *HIS_OUT, *HIS_ERR, p4 where $cmd);
print HIS_IN "stuff\n";
close(HIS_IN);            # Give end of file to kid.
my @outlines = <HIS_OUT>;    # Read till EOF.
my @errlines = <HIS_ERR>;    # XXX: block potential if massive
print "STDOUT:\n", @outlines, "\n";
print "STDERR:\n", @errlines, "\n";
print @errlines;
close HIS_OUT;
close HIS_ERR;
waitpid($childpid, 0);
if ($?) {
    print "That child exited with wait status of $?\n";
}

        if(@errlines eq 'file(s) not in client view')
        {
        push @changed_paths,"$file\n";
        }
}
[download]

You probably want to use IO::Select with the IPC3 filehandles, so you won't block. Look at this example, using the calculator program, bc. You can adapt your p4 to run this way.

#!/usr/bin/perl
use warnings;
use strict;
use IPC::Open3;
use IO::Select;

#interface to "bc" calculator
my $pid = open3(\*WRITE, \*READ,\*ERROR,"bc");

my $sel = new IO::Select();

$sel->add(\*READ);
$sel->add(\*ERROR);

my($error,$answer)=('','');

while(1){

 print "Enter expression for bc, i.e. 2 + 2\n";
 chomp(my $query = <STDIN>);
 
 #send query to bc
 print WRITE "$query\n";

 foreach my $h ($sel->can_read)
 {
   my $buf = '';
   if ($h eq \*ERROR)
   {
     sysread(ERROR,$buf,4096);
     if($buf){print "ERROR-> $buf\n"}
   }
   else
   {
     sysread(READ,$buf,4096);
     if($buf){print "$query = $buf\n"}
   }
 }
}

waitpid($pid, 1);
# It is important to waitpid on your child process,  
# otherwise zombies could be created.
[download]

---

I'm not really a human, but I play one on earth.
Old Perl Programmer Haiku ................... flash japh