setnodelay

Switch a handle’s descriptor to non-blocking reads (mode true) or back.

Synopsis

Term::ReadKey::setnodelay(\*STDIN, 1);
my $c = getc STDIN;                   # undef if nothing is waiting
Term::ReadKey::setnodelay(\*STDIN, 0);

What you get back

Always 0. ReadKey and ReadLine call it around a read with a negative timeout.