Re^2: Use of uninitialized value in open second time but not first.

So it actually spits a warning the first time.

Where does that warning go? It's not on my screen when I run it. As I see it, $output is uninitialized both times, but the warning is not printed the first time.

I'm confused also because what I pass to open is a reference to $output which is always a real value regardless of whether $output is initialized or not.

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Re^3: Use of uninitialized value in open second time but not first. by Bro. Doug (Monk) on Apr 01, 2007 at 16:29 UTC
I see where I went wrong. To give a more concise answer to this question, I got the code to run and saw the results just as you reported. So I started experimenting. I noticed there are a lot of operations on references happening here, which makes me leery when you're mucking with global symbols (STDOUT, for instance). So I took $output and gave it persistence in scope: `our $output ; # changed 'my' to 'our'` [download] The problem went away. By the way, I agree with the monks who suggested using select(). Peace, monks. Bro. Doug :wq	[reply] [d/l]

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Re^3: Use of uninitialized value in open second time but not first.
by Bro. Doug (Monk) on Apr 01, 2007 at 16:29 UTC

 our $output ; # changed 'my' to 'our'
[download]

Bro. Doug :wq

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