Pretend that this is your old program asking the questions. It doesn't do anything except ask them, read the answers and print out the names it read:

#! perl -slw
use strict;

print "enter file name  (you must specify the file name and press Ente
+r)";
chomp( my $infile = <STDIN> );

print "do you want to specify another file name (Y/N) (you must enter 
+N in most cases and press Enter)";
chomp( my $another = <STDIN> );

print "enter name for output file (you must specify a name for the out
+put file, eg ttt and press Enter)";
chomp( my $outfile = <STDIN> );

print "reading $infile; writing $outfile";

exit 99;
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Then you can drive that program from perl using something like this:

#! perl -slw
use strict;

my $progname = 'junk33';

my $pid = open CMD, '|-', $progname or die $!;

print CMD 'myInfile';
print CMD 'N';
print CMD 'myOutfile';

close CMD;

waitpid $pid, 0;

print "$progname ended: status: ", $? >>8;
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And when you run that, you'll see:

c:\test>junk32
enter file name  (you must specify the file name and press Enter)
do you want to specify another file name (Y/N) (you must enter N in mo
+st cases and press Enter)
enter name for output file (you must specify a name for the output fil
+e, eg ttt and press Enter)
reading myInfile; writing myOutfile
junk33 ended: status: 99
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