I want to read and write to a process (like tripwire) after polling its o/p, I am working on windows platform, Currently am trying open3 for that but the problem is that the message which Iam sending through "Print $wtr message", to my process is getting lost. here is the code,where I am passing valid date to date command after two invalid one but valid date is not getting accepted third time. 
use IPC::Open3;
use Symbol;
use FileHandle;
open ABC,">output.txt";
open DEF,">Eoutput.txt";
$WTR = gensym();  # get a reference to a typeglob
$RDR = ">&ABC";  # and another one
$ERRR = ">&DEF";  # and another one
$pid = open3($WTR, $RDR, $ERRR,'date');
STDIN->autoflush();
STDOUT->autoflush();
ABC->autoflush();
$WTR->autoflush();
print $WTR "3//3//3 \n";      
print $WTR "4//4/3 \n";     
print $WTR "4/5/3 \n";   
waitpid $pid,0;

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the o/p which iam getting is 
The current date is: Sat 04/05/2003 
Enter the new date: (mm-dd-yy) 3//3//34//4/34/5/3
The system cannot accept the date entered.
Enter the new date: (mm-dd-yy)

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all the three messages r getting concatenated then passed. but If i use "\n" in first print to process statement then i get 
The current date is: Sat 04/05/2003 
Enter the new date: (mm-dd-yy) 3//3//3
The system cannot accept the date entered.
Enter the new date: (mm-dd-yy)

[download]
the next two messages are getting lost, the o/p which iam expecting is 
The current date is: Sat 04/05/2003 
Enter the new date: (mm-dd-yy) 3//3//3
The system cannot accept the date entered.
Enter the new date: (mm-dd-yy) 4//4/3
The system cannot accept the date entered.
Enter the new date: (mm-dd-yy) 4/5/3

[download]

In reply to open3, process sychronization problem by brijeshsnm

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