goodie,

i have a billing software i wud like to customize but i dont know how to go about it. i know the first step is to get the source code but from there i pretty dont know much. i know i ll do a lot of editing but i want some advice. i also wud like to be able to generate license code for the software as well as i ll be selling it. Thanks

Loxie

Check the license! If it is GPL you must make the source available, effectively nullifying your sales effort. You can sell support but otherwise you are taking code written by others, on which they hold copyright, and selling it without their consent.

If the licence permits this (eg BSD) then take a crash cource in c

crash course in what?

AFAIK, GPL does allow you to sell your derived work as long as you make the modified source code available. Of course, it may not make a whole lot of business sense 'cause people can just take the source instead of paying you to obtain the binaries. Like you say, selling support is an alternative.

As for the modification itself, it depends upon how the original software is written.

its in .tar.gz format. hope that helps and am sure its written in c++

"tar.gz" is how the software is compressed. You can use the same formart to compress the modified version or use a different algorithm, such as bzip2. If it is written in C++, all you have to do is make your mods to the source files and rebuild/test your application to make sure it works the way you want it to before compressing the modified set of files for distribution.

hi thanks for ur messages Daihard,

am not really a newbie per se, when u "run ur mods on the source tree". where can i get to that, i ll need a type of environment to execute that and basically, its just to change the software names to the intended names and also put in a licensing code for users as well.

Thanks

I dont think you can just change its name and chrage people for it (atleast i hope you can't). You're effectively selling other peoples work (without permission?), without adding anything yourself, which is plain wrong.

Hard to know what OP is really up to......
I have seen several cases of OpenOffice being re-packaged and sold under different names. I had understood that this was legal--that the GPL basically says that what comes to you as open source must be maintained open.

True, but doesn't this depend on the licensing of the original software? without knowing that we couldn't advise, but, i am sure there is a moral dillema here...

Yes but that is all, provided the original software is GPL. GPL software is free, I can take GNU Screen, rename it to multiterm and sell that if I like. I must however include a copy of the license with all distrobutions and make the source available, essentially releasing it under the GPL as well.

On the other hand if it was released under something like the BSD license well then pffft. I can rename it, rebuild it and relicense it and not distribute source and do whatever the hell I liked.

Got too off topic I'm out now.

You can charge for GPL software but as pointed out in previous posts you must also make the source code available. Which seems to make the licencing module that debloxie wants to write somewhat pointless.

This also seems to go against one of Richard Stallman's freedoms: The freedom to run the software.

What billing software are you packaging up? What license is it under? If it's under BSD then go wild, though you still need to include the BSD copyright notice with it. If it's under GPL, then you can rename it, sell it, and even put in a license key requirement, but you'll need to also provide access to the source code and the modified software stays under the GPL license and provides the same freedom to your buyers as you got from the original author. If your buyers are smart they will realize what you are doing and won't buy anything from you unless you are providing added value to them.