You could also use Win32::GuiTest.

use Win32::GuiTest qw(FindWindowLike SetForegroundWindow SendKeys);
system("start p.bat");                 # start ensures that the progra
+m opens in a new window
sleep(1);                              # give p.bat a chance to load
my @win = FindWindowLike(0, "^p.bat"); # find p.bat's window (maybe mo
+re than one)
SetForegroundWindow($win[0]);          # bring the first p.bat window 
+to the foreground
SendKeys("y");                         # send a keypress to the active
+ window in this case a "y"
__DATA__
For this example, p.bat contains one line:
pause
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If the program doesn't accept the input from a pipe, it probably means that it is using direct access to the console or even simply flushing the input buffer prior to prompting.

As it's a console program, I'm not sure if Win32:CtrlGUI will succeed in feeding it input in the right way. If not, then you could also try using Win32::Console and the WriteInput(event) call. Be sure to use the STD_INPUT_HANDLE parameter for the new() call to get a handle to the existing console input buffer rather than creating a new one.

Even this may not work. For instance, if I was righting a program to accept a password from the console and I wanted to ensure that a human being was entering the password rather than a ghost writing program, I might create a new input console just for the purposes of retrieving that password without the FILE_SHARE_WRITE permission and discard it afterwards. In this case, there should be no way for any other program to 'feed' the input. Hopefully, a yes or no answer to a prompt won't have required such precautions:)

Good luck.

system ( "yes | foo" );
[download]

Makeshifts last the longest.

Cheers - L~R

Update: It appears that Win32 is only supported through Cygwin.

Perhaps the program you are executing is looking for a specific "any" key ;-) because this works for me...

system("echo y | pause");
__DATA__
C:\WINDOWS\Desktop>perl echo.pl
Press any key to continue . . .


C:\WINDOWS\Desktop>
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