Then i realized it was just a sub-second sleep. is that correct?

Yes.

http://perldoc.perl.org/functions/select.html suggests this select(undef, undef, undef, 0.001); instead.

Indeed. The empty strings version is just less typing; and appears to have no measurable affect on the functionality.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
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In reply to Re^3: Shared memory and asynchronous access by BrowserUk
in thread Shared memory and asynchronous access by vef445

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