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Is it ‘safe’ to use the IP address of 127.0.0.1 as the name of the local machine?

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21 Sep 2014 06:33 #2317 by support
If you can, leave the name blank. "127.0.0.1" should work, but it goes different ways internally, both inside QuickOPC, and inside Microsoft COM/DCOM.

Basically, whenever the machine name is not empty, it is (for most part) "unrecognizable" from representing a remote computer, and it is treated as such. It may mean less efficient access, and small differences in functionality.

One of the things that differ is that with an empty machine name, CoCreateInstance API call is used to instantiate the OPC objects; with a non-empty name, CoCreateInstanceEx is used, and this one takes many more parameters, regarding security etc. This stuff can hardly bring anything useful locally (and in some cases, it may even cause issues).
The following user(s) said Thank You: pgilbert

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21 Sep 2014 06:27 #2316 by support
From: P.
Sent: Friday, September 19, 2014 2:12 AM
To: Zbynek Zahradnik
Subject: RE: QuickOPC Download Form - ...

Hello Zbynek, [...] I have the following questions regarding the distribution and installation of your software while using it as COM:

[...]
4. Question 4: Is it ‘safe’ to use the IP address of 127.0.0.1 with ReadItemValue and WriteItemValue as the name of the local machine or you prefer to leave it blank ?

Thanks in advance,

P.

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