git-describe: what is the '-g' prefix good for?

Dirk Süsserott· Jul 16, 2009, 16:20 UTC · lore

Hello there,

I'm a bit surprised about the output of git-describe: if I'm on a tag, git-describe tells the tag's name. Fine. If I commit sth. on top of that, it tells how far I'm away from that tag and the current commit's SHA1. Very fine. But then the SHA1 is preceeded with a '-g'. What's that for?

I really don't want to ask for dropping it (I guess all people rely on it), but does anybody know about the initial intention of that '-g'? Cannot be easier parsing in porcelain scripts because either way the actual state is unambiguously.

Just a curious
     Dirk

Avery Pennarun· Jul 16, 2009, 17:47 UTC · re: Dirk Süsserott · lore

Re: git-describe: what is the '-g' prefix good for?

2009/7/16 Dirk Süsserott <newsletter@dirk.my1.cc>:

Show 5 quoted lines

> I'm a bit surprised about the output of git-describe: if I'm on a tag,
> git-describe tells the tag's name. Fine. If I commit sth. on top of
> that, it tells how far I'm away from that tag and the current commit's
> SHA1. Very fine. But then the SHA1 is preceeded with a '-g'. What's that
> for?

I'm sure it stands for something like "git". You don't want a random number appended to your tagname (which is often a version number) because it might be mistaken for part of the version number. The g makes this less likely. It also differentiates between git and any other version control system (except ones starting with 'g', I guess :)) that might implement a similar feature.

Avery