AFAIK, there's also a signal that gets sent in event of a power fluctuation. From there, you can use "ispoweron()" to tell the difference between a momentary power blip, and a real outage condition.

You'll only bother to poll when you've got a signal that said there was a potential outage issue, and then only to check to see if the situation has resolved itself (power back on or not). Depending on that knowledge, you can implement a variety of recovery policies (shutdown immediately; wait 10 minutes, then shutdown if the power is still out; etc).

From what I remember, it's not a useless function; albeit rarely very useful, either. AFAIK, it's been implemented on one of the BSD varients (BSDI Unix, perhaps?)

--
Ytrew

---

---

• Are you posting in the right place? Check out Where do I post X? to know for sure.
• Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:

  <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>

• Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
• Want more info? How to link or How to display code and escape characters are good places to start.