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@tst wrote:
As for what it does, it takes a binary string representing a VI and then loads that VI without going through the disk, returning a reference you can use. You could probably do this by writing that binary data to a file and then using Open VI Reference with that file path.
It sounds similar to Open VI with just a name? Those VIs should already be in memory i.e. in a buffer?
@Yamaeda wrote:
It sounds similar to Open VI with just a name? Those VIs should already be in memory i.e. in a buffer?
No no! It takes the binary data of a VI as it is saved in a file on disk but from a byte array buffer in memory. So basically VI Open Reference with a path parameter is more or less equal to:
- Read file from path into a memory buffer
- Call VI Open from Buffer with this memory buffer
It's the memory buffer streaming version of VI Open.
In reality it is more complex to make it more performant but still the principle is like that.
@rolfk wrote:
@Yamaeda wrote:
It sounds similar to Open VI with just a name? Those VIs should already be in memory i.e. in a buffer?
No no! It takes the binary data of a VI as it is saved in a file on disk but from a byte array buffer in memory. So basically VI Open Reference with a path parameter is more or less equal to:
- Read file from path into a memory buffer
- Call VI Open from Buffer with this memory buffer
It's the memory buffer streaming version of VI Open.
In reality it is more complex to make it more performant but still the principle is like that.
That's why i specified the String version with only a Name, there should be no file read on that one, right? Or am i missing something?
@Yamaeda wrote:
That's why i specified the String version with only a Name, there should be no file read on that one, right? Or am i missing something?
Well no of course not. It only works on VIs already in memory. But it references them by their name. This one is very different. The buffer contains the binary data of the VI. And the VI does not have to be already loaded. Basically think of it like a method to open a VI that you for instance received over some network communication as binary stream. Instead of having to write it onto disk and then open it from there, you can directly open it from the data in memory.
