FAQ 8.43 How do I open a file without blocking?

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This message is one of several periodic postings to comp.lang.perl.misc
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common questions. The core of this message represents an excerpt
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8.43: How do I open a file without blocking?

    If you're lucky enough to be using a system that supports non-blocking
    reads (most Unixish systems do), you need only to use the O_NDELAY or
    O_NONBLOCK flag from the Fcntl module in conjunction with sysopen():

        use Fcntl;
        sysopen(FH, "/foo/somefile", O_WRONLY|O_NDELAY|O_CREAT, 0644)
            or die "can't open /foo/somefile: $!":


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Re: FAQ 8.43 How do I open a file without blocking?

Quoted text here. Click to load it

I'm not sure I even understand what this is supposed to accomplish, but
wouldn't a better title be "How do I open a file for non-blocking reads?"?

As it stands, it sounds like it is the "open" (or "sysopen") itself that is
supposed to not block.


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Re: FAQ 8.43 How do I open a file without blocking?


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It might be. I've added the question to my queue and will think
about it when my brain isn't mush. :)

brian d foy, bdfoy@cpan.org
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