error in my perl code

I have the following code:

while (<INFILE> ) {
print OUTFILE;
}

The above code reads every line in my INFILE and writes it to the OUTFILE and works fine, but when I change it to the following it doesn't write anything to my OUTFILE ?

while (<INFILE> ) {
if ($_ eq "yes") {
print "$_";
print OUTFILE;
}
}

I only want to write those records to my outfile where the record ($_) = yes.

to print to the outfile you need to do this!

Code:

---

print OUTFILE $_;

---

Actually the following lines should be equivalent:

Code:

---

print OUTFILE $_;
print OUTFILE;

---

This being Perl, if you wanted to write a file to std out:

Code:

---

while (<INFILE> ) {
print;
}

---