NAME
----
-gittutorial-2 - A tutorial introduction to git: part two
+gittutorial-2 - A tutorial introduction to Git: part two
SYNOPSIS
--------
+[verse]
git *
DESCRIPTION
You should work through linkgit:gittutorial[7] before reading this tutorial.
The goal of this tutorial is to introduce two fundamental pieces of
-git's architecture--the object database and the index file--and to
+Git's architecture--the object database and the index file--and to
provide the reader with everything necessary to understand the rest
-of the git documentation.
+of the Git documentation.
-The git object database
+The Git object database
-----------------------
Let's start a new project and create a small amount of history:
$ git add .
$ git commit -a -m "initial commit"
[master (root-commit) 54196cc] initial commit
- 1 files changed, 1 insertions(+), 0 deletions(-)
+ 1 file changed, 1 insertion(+)
create mode 100644 file.txt
$ echo 'hello world!' >file.txt
$ git commit -a -m "add emphasis"
[master c4d59f3] add emphasis
- 1 files changed, 1 insertions(+), 1 deletions(-)
+ 1 file changed, 1 insertion(+), 1 deletion(-)
------------------------------------------------
-What are the 7 digits of hex that git responded to the commit with?
+What are the 7 digits of hex that Git responded to the commit with?
We saw in part one of the tutorial that commits have names like this.
-It turns out that every object in the git history is stored under
+It turns out that every object in the Git history is stored under
a 40-digit hex name. That name is the SHA1 hash of the object's
-contents; among other things, this ensures that git will never store
+contents; among other things, this ensures that Git will never store
the same data twice (since identical data is given an identical SHA1
-name), and that the contents of a git object will never change (since
+name), and that the contents of a Git object will never change (since
that would change the object's name as well). The 7 char hex strings
here are simply the abbreviation of such 40 character long strings.
Abbreviations can be used everywhere where the 40 character strings
the one shown above because the commit object records the time when
it was created and the name of the person performing the commit.
-We can ask git about this particular object with the `cat-file`
+We can ask Git about this particular object with the `cat-file`
command. Don't copy the 40 hex digits from this example but use those
from your own version. Note that you can shorten it to only a few
characters to save yourself typing all 40 hex digits:
hello world
------------------------------------------------
-Note that this is the old file data; so the object that git named in
+Note that this is the old file data; so the object that Git named in
its response to the initial tree was a tree with a snapshot of the
directory state that was recorded by the first commit.
-All of these objects are stored under their SHA1 names inside the git
+All of these objects are stored under their SHA1 names inside the Git
directory:
------------------------------------------------
is a "tag", which we won't discuss here; refer to linkgit:git-tag[1]
for details.
-So now we know how git uses the object database to represent a
+So now we know how Git uses the object database to represent a
project's history:
* "commit" objects refer to "tree" objects representing the
+hello world, again
------------------------------------------------
-So 'git-diff' is comparing against something other than the head.
+So 'git diff' is comparing against something other than the head.
The thing that it's comparing against is actually the index file,
which is stored in .git/index in a binary format, but whose contents
we can examine with ls-files:
hello world, again
------------------------------------------------
-So what our 'git-add' did was store a new blob and then put
+So what our 'git add' did was store a new blob and then put
a reference to it in the index file. If we modify the file again,
-we'll see that the new modifications are reflected in the 'git-diff'
+we'll see that the new modifications are reflected in the 'git diff'
output:
------------------------------------------------
+again?
------------------------------------------------
-With the right arguments, 'git-diff' can also show us the difference
+With the right arguments, 'git diff' can also show us the difference
between the working directory and the last commit, or between the
index and the last commit:
+hello world, again
------------------------------------------------
-At any time, we can create a new commit using 'git-commit' (without
+At any time, we can create a new commit using 'git commit' (without
the "-a" option), and verify that the state committed only includes the
changes stored in the index file, not the additional change that is
still only in our working tree:
+again?
------------------------------------------------
-So by default 'git-commit' uses the index to create the commit, not
+So by default 'git commit' uses the index to create the commit, not
the working tree; the "-a" option to commit tells it to first update
the index with all changes in the working tree.
-Finally, it's worth looking at the effect of 'git-add' on the index
+Finally, it's worth looking at the effect of 'git add' on the index
file:
------------------------------------------------
$ git add closing.txt
------------------------------------------------
-The effect of the 'git-add' was to add one entry to the index file:
+The effect of the 'git add' was to add one entry to the index file:
------------------------------------------------
$ git ls-files --stage
#
# new file: closing.txt
#
-# Changed but not updated:
+# Changes not staged for commit:
# (use "git add <file>..." to update what will be committed)
#
# modified: file.txt
At this point you should know everything necessary to read the man
pages for any of the git commands; one good place to start would be
-with the commands mentioned in link:everyday.html[Everyday git]. You
+with the commands mentioned in link:everyday.html[Everyday Git]. You
should be able to find any unknown jargon in linkgit:gitglossary[7].
The link:user-manual.html[Git User's Manual] provides a more
-comprehensive introduction to git.
+comprehensive introduction to Git.
linkgit:gitcvs-migration[7] explains how to
-import a CVS repository into git, and shows how to use git in a
+import a CVS repository into Git, and shows how to use Git in a
CVS-like way.
-For some interesting examples of git use, see the
+For some interesting examples of Git use, see the
link:howto-index.html[howtos].
-For git developers, linkgit:gitcore-tutorial[7] goes
-into detail on the lower-level git mechanisms involved in, for
+For Git developers, linkgit:gitcore-tutorial[7] goes
+into detail on the lower-level Git mechanisms involved in, for
example, creating a new commit.
SEE ALSO
linkgit:gitcore-tutorial[7],
linkgit:gitglossary[7],
linkgit:git-help[1],
-link:everyday.html[Everyday git],
+link:everyday.html[Everyday Git],
link:user-manual.html[The Git User's Manual]
GIT