If you are on Win32, you are just out of luck. But if you are on unix/linux you can set the filehandle to non-blocking. This will let you read from the handle if something is there. If nothing is there it will continue on to the next line of code.

use Fcntl;

my $flags;
fcntl(FILEHANDLE, F_GETFL, $flags) || die $!; # Get the current flags 
+on the filehandle
$flags |= O_NONBLOCK; # Add non-blocking to the flags
fcntl(FILEHANDLE, F_SETFL, $flags) || die $!; # Set the flags on the f
+ilehandle
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