Tropo is part of CiscoLearn More

Unnamed Signals

If you don't provide a function with a signal (or a list of signals), it will be interrupted by any signal sent to the API; the default value of allowSignals is essentially a wildcard. This allows you to send a signal to interrupt a Tropo function without telling Tropo ahead of time that you intend to interrupt the function. The say in this app can be interrupted by any signal:

say("http://www.example.org/holdmusic.mp3");
say "http://www.example.org/holdmusic.mp3"
<?php
say("http://www.example.org/holdmusic.mp3")
?>
say("http://www.example.org/holdmusic.mp3")
say("http://www..example.org/holdmusic.mp3")

However, if you specifically define allowSignals using "", this will be interpreted as "never interrupt" instead:

say("http://example.org/holdmusic.mp3", {
    allowSignals: ""
});
say "http://example.org/holdmusic.mp3", {
    :allowSignals => ""
    }
<?php
say("http://example.org/audio/holdmusic.mp3", array(
    "allowSignals" => ""
));
?>
say("http://example.org/holdmusic.mp3", {
    "allowSignals": ""
})
say("http://example.org/holdmusic.mp3", [
    allowSignals: ""
])