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Re: Testing for filehandles

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Chas Owens
March 27, 2002 13:41
Re: Testing for filehandles
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On Wed, 2002-03-27 at 15:18, wrote:
> Hello, All:
> I've looked around for an answer to this (The Camel Book, The Ram Book, 
> perldoc,, etc.) but can't find a thing: Is it possible to test 
> for the existence of a filehandle?
> I've got a small script that <optionally> opens a filehandle. If that 
> filehandle exists, I'd like to print to it. Otherwise, don't. e.g.,
> use Getopts::Std;
> getopts("n");
> open(OPT_LOG,">/tmp/foo.txt") if ($opt_n);
> while (<>) {
> 	print OPT_LOG $_ if OPT_LOG;
> }
> close(OPT_LOG) if OPT_LOG;
> -- 
> Eric P.
> Los Gatos, CA

What you want is select (assuming you want the output to go to the
screen if they don't specify a file).  See "perldoc -f select".

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