Re: Git terminology: remote, add, track, stage, etc.

From: Nicolas Pitre <nico@fluxnic.net>
Date: Oct 19, 2010, 19:15 UTC
Message-ID: <alpine.LFD.2.00.1010191508370.2764@xanadu.home>
In-Reply-To: <0B20EFC4-E613-4D4A-B4F8-8B1750AA8AFD@gmail.com>

On Tue, 19 Oct 2010, Thore Husfeldt wrote:

Show 27 quoted lines

> Also, in the user-manual.txt:
> 
> > Examining branches from a remote repository
> > -------------------------------------------
> > 
> > The "master" branch that was created at the time you cloned is a copy
> > of the HEAD in the repository that you cloned from.  That repository
> > may also have had other branches, though, and your local repository
> > keeps branches that track each of those remote branches, which you
> > can view using the "-r" option to linkgit:git-branch[1]:
> > 
> > ------------------------------------------------
> > $ git branch -r
> >   origin/HEAD
> >   origin/html
> >   origin/maint
> >   origin/man
> >   origin/master
> >   origin/next
> >   origin/pu
> >   origin/todo
> > ------------------------------------------------
> > 
> > You cannot check out these remote-tracking branches, but you can
> > examine them on a branch of your own, just as you would a tag:
> 
> That’s just wrong, isn’t it? You absolutely can check out a remote-tracking branch.--

Yes, the above is wrong. But to check out a remote-tracking branch, or a tag, or a random commit through its SHA1, we do rely on the concept of a "detached head". That term and concept has caused newbies grief in the past as well, despite the fact that seasoned Git users are perfectly fine with it.

A detached head is HEAD not being linked to any branch. This is done because tags and remote-tracking branches are not meant to be altered by local changes. Hence committing stuff on top of a detached head will advance HEAD, but no actual branch is keeping a record of it.

Nicolas