For more complex cases where you may get different sequences of prompts, I would recommend the Expect module.

use strict;
use Expect;
...

# This sample code is adapted from the Expect man page,
# and is not tested.
my $exp = Expect->spawn($command, @params)
  or die "Cannot spawn $command: $!\n";
$exp->send("string\n");
my ($matched_pattern_position,
    $error,
    $successfully_matching_string,
    $before_match,
    $after_match) =
    $exp->expect($timeout, @match_patterns);
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