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I would like to use a dynamically linked library with GPL V2 license for adding remote support to my existing C++ application. I use the library without modifications of the library code.
Do I need to use GPL license for my program or do I need only to give access to the library license and code?
Is there a possibility to create an own library using the library under GPL with another license like LGPL?
The jury is still out on this one.
The traditional interpretation, and the one intended by the Free Software Foundation(FSF, publishers of the GPL), is that no, you can't do this. This position seems to have broad support. Both parts of your question are dealt with in the GPL FAQ.
The first, if it "counts" if you link dynamically has it's own section in the FAQ. It answer is that it doesn't matter whether you link statically or dynamically, it's all governed by the GPL.
The second, can you make an LGPL wrapper is dealt with in another section of the FAQ. It answers that you can't do this.
This view is what the intention of the GPL is, and also seems to be the most common view. It's not the only view though.
Some claim that dynamic linking doesn't make a work that has to be licensed under the GPL, or doesn't always make a work that has to be licensed under the GPL.
Lawrence Rosen, General council of the OSI, argued in the Linux journal that whether or not it's linked statically or dynamically doesn't matter, but that linking to a library does not create a derivative work, and is not bound to the GPL.
It should be noted that both the OSI position and the FSF position have a measure of partizanship in what they regard as what "the right thing" with regard to open source/free software is.
As long as there is no case law on the subject with a definitive outcome - and there isn't any just yet - legally this is still an open question. The safe route is to take the most conservative, that is, the position the FSF takes.
Lastly, two caveats:
If this is for personal use, and you don't intend to distribute the result, then you can always do this, and the rest of the answer is void. This only comes in to play if you distribute the end result.
Throughout the answer, I've equated "commercial use" to "propriety licensed". That's not completely right; you may distribute open source software commercially, but since anyone can fork and distribute the product, there are large challenges in setting up a business model for it.
It depends on the views of the copyright owner as to the definitions of derived work versus aggregation. The FSF themselves take a very broad view of derived work that would forbid your use case; they specifically see shared lib inclusion as creating a derived work. Other organizations have different views. It has never been litigated, so no one knows for sure what will happen if you do this for when the copyright owner shares the FSF's views.
Yes, but then you have to abide by the GPL for the composite. I.e., give full source to whoever gets binaries, and place no restrictions on further binary/source distribution by the recipient.
Check the conditions GPL imposes, also read the supporting/explanation documents from the FSF.
