Re: RFE: allow for computed version number

[Ralf Wildenhues]

Hi Bob,

* Bob Friesenhahn wrote on Fri, Jun 05, 2009 at 06:54:16PM CEST:
> On Fri, 5 Jun 2009, Peter Johansson wrote:
>> Bob Friesenhahn wrote:
>>> Doesn't any approach which depends on an automatically generated file 
>>> assure that the version control system is one step out of date? Every 
>>> time you do a 'commit' the version file is one step newer and 
>>> therefore needs to be committed.
>>
>> Your analysis seems to assume that you commit the version file into the VCS.
>
> Yes.  It assumes the model where anyone who receives the package has the 
> ability to build and maintain it similar to the original maintainer.  

But whether the file is distributed in a package tarball or not is
independent of whether the file is put into the VCS or not.

> Some might say that the ability for independent maintenance is part of 
> the essence of free software.  There are complexities if an active 
> version control system (with particular access and user rights) needs to 
> be available in order to produce a release.  It can be easily argued that 
> if a particular instance of a particular version control system is 
> required, that satisfying GPL requirements becomes problematic since the 
> VCS becomes part of the "build scripts" which are required to be 
> delivered.

Well, this line of thought is actually an argument in favor of putting
the version in a file, not putting that file in VCS, but in a
distribution tarball.  That way, the user of the tarball does _not_ need
the VCS, because the file will be up to date, and `cat version-file`
will work even where `git describe` will not.

> If the version comes from a version control system change set ID, and  
> the version info is also distributed in a file, then the version in the 
> distributed file will always be behind what the value would be if it was 
> comitted.

Again, you are mixing up committing the file with distributing it here.
As long as the distribution tarball is generated by 'make', it is
trivially possible to ensure the version file is up to date before
making the tarball.

Cheers,
Ralf