Then you are using it wrong!

Using the perl script as a substitute for your runme.exe:

#! perl -slw
use strict;

printf "%030d\n", $_ for 1 .. 1e3;
print "Press enter to exit";
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And this Perl script to run the above using winopen2():

#! perl -slw
use strict;
use Win32::Socketpair qw[ winopen2 ];

## Run the command and get a bi-direction pipe to it.
my $pipe = winopen2( 'RunMe.pl' );
my @results = <$pipe>;
print $pipe "\n";

print scalar @results;

<STDIN>;
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The latter reads a thousand lines from the former, sends "\n" to it which allows it to end, and then prints out the number of lines read (1001 including the "Press Enter to exit prompt") amd waits. If you check the task manager you'll see that the child process has terminated:

[12:05:50.87] C:\test>winopen2-test.pl
1001


[12:06:00.23] C:\test>
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This is my Script:

use strict;
use warnings;
use Win32::Socketpair qw[ winopen2 ];

## Run the command and get a bi-direction pipe to it.
my $pipe = winopen2( 'PwrUsbCmd.exe 0 0 0' );
my @results = <$pipe>;
print $pipe "\n";
print @results;
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It is not working. The Output from 'PwrUsbCmd.exe' is:

PowerUSB is not connected
Enter to continue ## Here I have to press enter to exit from this EXE 
+and it is not working.
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I think I've managed to re-create the situation you are seeing. I believe you are suffering from buffering.

Please try the following code and report your results. This isn't intended as a complete solution, but rather a diagnostic to understand your problem.

#! perl -slw
use strict;
use Win32::Socketpair qw[ winopen2 ];

## Run the command and get a bi-direction pipe to it.
my( $pid, $pipe ) = winopen2( 'RunMe.exe',  $ARGV[0 ] // 10 );

## preload the childs input buffer with the answer to the prompt;
print $pipe "\n";

## give the kid a chance to say whatever it has to say
sleep 2;

## a nonblocking read to grab whatever has made it through the buffers
## which if the kid produced less output than the size of its output b
+uffer
## and didn't flush them, may be nothing at all
my $results = '';
sysread( $pipe, $results, 65536, length $results );

close $pipe;

print for split "\n", $results; ## May produce no output
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---

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

The start of some sanity?