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VW 7.4 Synchronizes Its Clock

Cincom didn't publicize it, but VW 7.4 includes a fix that may be quite useful in some situations.

In previsous versions, once an image had started running, the count of microseconds returned by primitive 351 (or the count of milliseconds returned by primitive 350, in versions of VW prior to VW7) was unaffected by any adjustments made to the host platform's system clock. So, if an NTP service was running that kept the host system's clock synchronized with a time server, any running VW image would receive no benefit. Clock adjustments from any source (including the user) were invisible to a running VW image.

Most computer clocks are not all that accurate. They can diverge from accurate time by minutes per month. Such inaccuracy may be acceptable to many, but to some it is not. There are technical, scientific, legal and even business use cases that must have a clock with much greater accuracy. Having "legally traceable time" may be the difference between winning and losing a lawsuit.

But as of VW 7.4, VisualWorks will be useable in use cases where time must be accurately kept within subsecond tolerances over long periods of time, without requiring an expensive, non-standard clock device.

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