i have a test script that i use for getting feedback from a display controller... to basically check for buffer high or buffer low (which is preset) while testing the display. i am using sysread to do this. however sysread may hang if neither of the two cases are true for the controller. i want to incorporate a timeout so that the code skips and continues to send data to the display. 

$buffer_high = 255;
$buffer_low = 254;

sub process_lcd {
  ...

  my $key = sysread (DisplayIO, $lcdValue, 1);

  return $lcdValue;

} # end process_lcd

# code then compares values for $lcdValue with $buffer_high and $buffe
+r_low

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the code hangs indefinitely at sysread. i wish to put a 1/500th sec timeout around the sysread.. thanks for your help in advance..

In reply to exiting sysread if no input by perllearner

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