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I am working on a security camera system as a favour for some people I know. One aspect of the system is that, once movement is detected, a phone number is called (I am not trying to spam call anyone :-)

I need to know a way to automatically dial a phone number.

The computer running the system runs linux, and has internet access, but does NOT have physical access to a phone jack so I cannot use a local modem. Either it must have some agent on the local area network do the dialing, or use the internet in some way.

I looked into using the Skype API, but that was a massive mess and people are no longer allowed to access the developer site as it's supposedly being revamped.

The other solution I am investigating is having a network-connected microcontroller talk to a serial modem, but this seems awfully complicated for something that should be so easy.

Any suggestions would be greatly appreciated, thank you.

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If you're looking for a solution that relies on a web service, you'll be better off asking on Web Applications Stack Exchange. I recommend saying which country you're in. – Gilles Dec 13 '10 at 21:06

Is the number a cell phone? If so you could send it a text message using an SMS gateway.

It looks like you may be able to so with Google Voice as well via email.

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The way the alarm monitoring company works, it must be a phone call, and unfortunately Google Voice does not operate in my country. – Will Dec 13 '10 at 22:32

1) Decide your basic need. My guess:

  • Notify one or more people by phone (because that is the device they have with them) of a security issue.

2) Brainstorm a variety of ways to accomplish that. Thoughts:

  • Modem to dial the number and then make a pattern of beeps at them.
  • VOIP system to automatically play a specific audio file over the phone.
  • Text messages (a few email-to-text gateways or the like out there)
  • Email (for those who get email on their devices).
  • other?

3) Evaluate each option you came up with and pick the one that fits the best (cost, features, etc.)

I suspect text messages might end up being the simplest approach. Modems not for two reasons (too far from a jack, + the message you can send is imprecise at best.)

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Absolutely this can be done with skype. And quite easily:

On Linux, the CLI for Skype is as follows:

"skype --callto echo123"

Java code:



public class SkypeEchoTest {

    public static void main(String args[]) throws IOException {
        String s = null;
        Process p = Runtime.getRuntime().exec("skype --callto echo123");
        BufferedReader stdInput = new BufferedReader(new InputStreamReader(p.getInputStream()));
        System.out.println("Here is the standard output of the command:\n");
        while ((s = stdInput.readLine()) != null) {

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