Updated 2016-09-20 11:35:23 by dbohdan

This pages discusses software licenses in general.

See Also  edit

information about the Tcl license in particular

Reference  edit

Licensing HOWTO, by Eric S. Raymond
discusses the legal issues of licensing at quite some length.
No Easy Fix for Open Source Licensing Issues, Glen Kunene, 2005-02-02
open-source licenses, Open Source Initiative
The FSF has its disagreements with the OSI.
What are all the different license types?
Assistance requested in developing Free SW license for Tcl extension, comp.lang.tcl, 2002-04-09
How to choose a free software license, Per Abrahamsen
makes an argument against developers trying to invent their own licenses
Why Isn't ODBC a Standard Feature of Linux?, Jon Udell, 1999-11-03
illustrates the difference between GPL and LGPL

Choosing a License  edit

If you are a software author, you should think carefully about what kind of end-user license agreement (or EULA in legal parlance) you use. You might consider what category your work falls under and how you want people to use it:
a useful, complete application that does something for an end user. Both GPL and BSD style licenses work here, depending on whether you are worried about someone else adding some proprietary changes to your code and releasing it publically.
some code that by itself is not useful, but can be combined with other libraries and code to create an application. The BSD or at least LGPL would be much appreciated by your fellow developers so they can use the code, even in proprietary projects, without worries.

See also Open Source.

Tcl Extensions  edit

For the purposes of this information, "extension" refers to any script written in the Tcl language, and also programs tht emply the Tcl C API.

The Tcl/Tk license imposes no restrictions on the author of a Tcl extension as to copyright ownership of the extension, or as to how the extension may be licensed.

The TCT encourages extension authors to use a BSD-related license similar to the one used in Tcl/Tk/tcllib/tklib/etc. as some companies find it less restrictive than the GPL or LGPL.

General Tips  edit

Whenever you begin hacking on someone else's code, it is always good to know the term under which that code is licensed, and what the implications are for your modifications.

Licenses  edit

Requires the licensee pretty much just to give you credit. Comes in a 2-clause and a 3-clause flavour. The 3-clause flavour has a "you can't use my name to promote your product" clause.
Substantially similar to the 2-clause BSD.
Requires all derivative works also to be licensed under the GNU GPL or a compatible license.
Like the GPL, but doesn't propagate its terms to software that merely links against LGPL-licensed software.

Minimal Licenses  edit

Limited Obligation Licence
No Obligation Licence
One Line Licence

Discussion  edit

escargo 2005-05-24: Licenses, like many other kinds of policies, are usually reactions to some kind of problem. I think it might be useful to try to determine what problems different licenses are trying to solve, and then compare the different problems. (For example, I would say the Gnu Public License is trying to solve the problem of people using code to create products from available code without making the changes available.)

Lars H: Could anyone natively-English-speaking comment on the two spellings "licence" and "license"? Looking in a printed dictionary (these tend to be more reliable than the net in such matters) I find "licence" listed primarily as a noun, whereas "license" is only listed as a verb. Yet I see both used as nouns all over!

WordNet (r) 2.0 licence

noun 1: excessive freedom; lack of due restraint; "when liberty becomes license dictatorship is near"- Will Durant; "the intolerable license with which the newspapers break...the rules of decorum"- Edmund Burke [syn: license]

2: freedom to deviate deliberately from normally applicable rules or practices (especially in behavior or speech) [syn: license]

3: a legal document giving official permission to do something [syn: license, permit]

verb 1: authorize officially; "I am licensed to practice law in this state" [syn: license, certify] [ant: decertify]

LV: Well, I speak American English, and people I know here are frequently poor spellers, and likely to spell the word which ever way seems to come out of their fingers at the moment.

I don't recall during any schooling any discussion or argument regarding the use of one spelling versus the other.

Perhaps our British readers might chime in here from their perspective.

MG: According to my OED, in en_uk licence is a noun and license can be a verb or a noun. It also says that in en_us, license can be either a verb or a noun, and licence is just a verb. I tend to just use 'license' for everything, myself...

RS ponders that for the noun, both forms derive from Latin licentia...

MJL: In (British) English, licence is the noun and license is the verb. The suffixes are the same in the pair practice/practise. My understanding is that in American English there is only one spelling - license (also practice) - for both noun and verb.