FAQ 8.43 How do I open a file without blocking?

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This is an excerpt from the latest version perlfaq8.pod, which
comes with the standard Perl distribution. These postings aim to
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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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