General question about open source development

raphasauer

If someone wants to use Qt for an open source project, they must adhere to certain conditions (LGLP), such as:

Freedom to run the program for any purpose.
Freedom to study how the program works & adapt it to specific needs.
Freedom to redistribute copies so you can help your neighbor.
Freedom to improve the program & release your improvements to the public, so that the whole community benefits.

Imagine that a application divided into parts, such as box A and box B. They are connected somehow. Box A uses Qt to show cute things on the screen, and box B does magic to be shown on the screen. Do you need to release both boxes' full code or you can just release Box A's code?

SGaist

Hi,

You are mixing LGPL and GPL.

LGPL does not require you to disclose your code. Your users shall be able to switch your LGPL dependencies for a different version and you shall publish the changes you made to your LGPL dependencies beside providing an easy to access acknowledgement for these dependencies.

raphasauer

@SGaist so it's more to do with what one has changed on Qt's libraries?

SGaist

If you are using the LGPL license, yes.

Note that this is not specific to Qt.

Anonymous_Banned275

@SGaist said in General question about open source development:

LGPL

So what is the purpose of "Lesser " license?
It implies there are other , perhaps "More" as oppose to "Less" licenses .
If the "coder" produced stuff he /she is NOT , by LGPL" , required to publish , what is the point to "license it "?
If the coder is not required to publish , then does it imply if he does publish anyway , he / she is NOT obligated to document / comment his /hers creation ?

If licensing is to provide legal "protection' of "(intellectual ) property " - the bottom line being "you should not make money using somebody else property" .

But if you give credit , you are licensed to use it - hence possibly make money..

I am not going to bother reading the fine print of LGPL - but it seems to be missing the primary purpose of license as stated above.

JKSH

@AnneRanch said in General question about open source development:

it seems to be missing the primary purpose of license as stated above.

Your view of licenses is based on traditional commerical licensing. GPL licensing has a different primary purpose.

The purpose of traditional commercial licensing is to protect intellectual property of the software author.
The purpose of free software licensing is to protect the freedoms of the software user.

It implies there are other , perhaps "More" as oppose to "Less" licenses .

That's right.

The GPL protects lots of user freedoms.
The Lesser GPL protects less user freedoms than the GPL.

So what is the purpose of "Lesser " license?

Traditional commercial software authors can't take the GPL, but they can sometimes take the LGPL.

Anonymous_Banned275

This post is deleted!

JKSH

@AnneRanch said in General question about open source development:

@JKSH So if the "author" has no obligation to publish - how does that "protect" the user ?
If it is bad product I can see the "protection" , but it should be up to the user to decide.

In any case - there is something amiss in the concept of "free licensing" - it is like writing a book and not publish it. Silly.

You'll find there's nothing amiss when you understand its goals.

If an application/executable is a house, and the source code is the blueprints, then a traditional commercial license is like a property developer that says: "Pay me money and you can live in this house. But you are not allowed to look at the blueprints, you are not allowed to renovate or repair the house, and you are not allowed to replace even a single lightbulb."

Now, suppose someone invents a fancy home automation system.

If this system is released under the GPL, it says to the property developer, "You can use my system in the houses that you build. In return, you must give your buyers the blueprints (including the schematics of my automation system) and give them permission to renovate/repair/replace all parts of the house."
If this system is released under the Lesser GPL, it says to the property developer, You can use my system in the houses that you build. In return, you must give your buyers access to the schematics of my automation system and give them permission to tinker with and replace the automation system.

So, when the inventor releases the home automation system under the GPL/LGPL, they are encouraging property developers to give the homebuyers more freedom.