I ran your code on my system (with a "newfile.c" that had four lines), and I had no problem. If I run with a file that has only one line, I get the output you get. In that case, when you do: 

$line=<HANDLE2>;

[download]

...$line contains undef because HANDLE2 is, like HANDLE1, at end of file.

Then when you use line in the following print: 

print "hello $line\n";

[download]

That's when you get the warning. Note that you'd get the warning any time you try to interpolate that variable (carrying the special undef value), even if it's not being printed.

In reply to Re: uninitialized value warning and duplicating file handles by kyle
in thread uninitialized value warning and duplicating file handles by perlplayer

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