I was hoping that Perl would turn an 'undef' for $timeout into a NULL pointer and '0' for $timeout into a struct timeval with a 0 value, but I hadn't tested it. One of the comments in the earlier thread Re: Re: Non blocking read on a filehandle indicated it wasn't working then (back in 2001).

In reply to Re^3: How to tell if a pipe opened for reading has data to be read by saintly
in thread How to tell if a pipe opened for reading has data to be read by Anonymous Monk

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