Legal jargon? If PP uses the LinuxCNC engine to accomplish the task of running their equipment then IMHO, "aggregate" is a joke.
Their PP couldn't exist by itself and be useful running hardware without LinuxCNC and the tens of thousands of hours of development that brought LinuxCNC up from nothing so many years ago is used to help a company sell equipment. But it sounds like it's available to some developers so moot point I guess. But truthfully I don't care. Don't know if I want the PP interface because I don't know how ot try it out. LinuxCNC isn't as easy to change a user interface as MACH3 is so I'm not even sure how I'd install and run it even if I did have the code. In MACH3 select the menu 'view' load a .set file and get a new user interface. The .set file sits in the root folder for MACH3 and the png files for the various buttons etc in a folder below that. Is it as extensible as LinuxCNC? I doubt it. LinuxCNC in the long run is way more versatile. Is MACH3 easier to use to try different interfaces? Without a doubt. John > -----Original Message----- > From: Chris Albertson [mailto:albertson.ch...@gmail.com] > Sent: June-11-19 12:14 PM > To: Sebastian Kuzminsky; Enhanced Machine Controller (EMC) > Subject: Re: [Emc-users] LinuxCNC and Tormach > > Path Pilot is what GNU calls an "aggregate�. This is why I pointed > out about the address space. Because GNU makes a distinction based > on that. > The software Tormach delivers is an aggregate and some of it is > covered by GPL, some of it not covered. Tormach claims there user > interface is a separate program that uses a standard interface to > Linux CNC. I don't have PP so I can't examine. > > But if you have a running copy, look and see how the data is > exchanged. Is it via a standard interface like g-code or it is a > large complex shared data structure? > > ++++ QUOTE from gnu.org web site follows ++++ > > > What is the difference between an �aggregate� and other kinds of > �modified versions�? (#MereAggregation) > > An �aggregate� consists of a number of separate programs, distributed > together on the same CD-ROM or other media. The GPL permits you to > create and distribute an aggregate, even when the licenses of the > other software are nonfree or GPL-incompatible. The only condition is > that you cannot release the aggregate under a license that prohibits > users from exercising rights that each program's individual license > would grant them. > > Where's the line between two separate programs, and one program with > two parts? This is a legal question, which ultimately judges will > decide. We believe that a proper criterion depends both on the > mechanism of communication (exec, pipes, rpc, function calls within a > shared address space, etc.) and the semantics of the communication > (what kinds of information are interchanged). > > If the modules are included in the same executable file, they are > definitely combined in one program. If modules are designed to run > linked together in a shared address space, that almost surely means > combining them into one program. > > By contrast, pipes, sockets and command-line arguments are > communication mechanisms normally used between two separate programs. > So when they are used for communication, the modules normally are > separate programs. But if the semantics of the communication are > intimate enough, exchanging complex internal data structures, that too > could be a basis to consider the two parts as combined into a larger > program. > > On Tue, Jun 11, 2019 at 11:45 AM Sebastian Kuzminsky > <seb.kuzmin...@gmail.com> wrote: > > > > On 6/11/19 11:33 AM, Chris Albertson wrote: > > > Was Path Pilot linked into the LinuxCNC address space? > > > > To be clear, LinuxCNC is a multi-process application, so there are > > several address spaces, not just one. > > > > Path Pilot is a Python application that imports several python modules > > that are part of LinuxCNC (the module are: linuxcnc, hal, and gremlin). > > These LinuxCNC python modules are required in order to interface to the > > LinuxCNC motion controller, and exchange commands, status, and error > > information. > > > > > > > To be a derivative work it must be running in the same address > > > space. If PP runs as a different process it is not covered by GPL. > > > > I disagree. > > > > From the GNU FAQ, > > https://www.gnu.org/licenses/old-licenses/gpl-2.0- > faq.html#MereAggregation: > > > > > ... if the semantics of the communication are intimate enough, exchanging > > > complex internal data structures, that too could be a basis to > > > consider the two parts as combined into a larger program. > > > > > > > > -- > > Sebastian Kuzminsky > > > > -- > > Chris Albertson > Redondo Beach, California > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
