git
git-add
git-annotate
git-apply
git-archive
git-bisect--helper
git-blame
git-branch
git-bundle
git-cat-file
git-check-attr
git-checkout
git-checkout-index
git-check-ref-format
git-cherry
git-cherry-pick
git-clean
git-clone
git-commit
git-commit-tree
git-config
git-count-objects
git-describe
git-diff
git-diff-files
git-diff-index
git-diff-tree
git-fast-export
git-fetch
git-fetch-pack
git-fmt-merge-msg
git-for-each-ref
git-format-patch
git-fsck
git-fsck-objects
git-gc
git-get-tar-commit-id
git-grep
git-hash-object
git-help
git-index-pack
git-init
git-init-db
git-log
git-ls-files
git-ls-remote
git-ls-tree
git-mailinfo
git-mailsplit
git-merge
git-merge-base
git-merge-file
git-merge-index
git-merge-ours
git-merge-recursive
git-merge-subtree
git-merge-tree
git-mktag
git-mktree
git-mv
git-name-rev
git-notes
git-pack-objects
git-pack-redundant
git-pack-refs
git-patch-id
git-peek-remote
git-prune
git-prune-packed
git-push
git-read-tree
git-receive-pack
git-reflog
git-remote
git-remote-ext
git-remote-fd
git-replace
git-repo-config
git-rerere
git-reset
git-revert
git-rev-list
git-rev-parse
git-rm
git-send-pack
git-shortlog
git-show
git-show-branch
git-show-ref
git-stage
git-status
git-stripspace
git-symbolic-ref
git-tag
git-tar-tree
git-unpack-file
git-unpack-objects
git-update-index
git-update-ref
git-update-server-info
git-upload-archive
git-var
git-verify-pack
git-verify-tag
git-whatchanged
git-write-tree
所有这些目标都是相同的大小:4951925，它们的内容是相同的，为什么?
[root@ git-1.7.6]$ ls -il /usr/bin/git*
17823222 lrwxrwxrwx 1 root root 22 2011-01-24 11:43 /usr/bin/git -> /usr/local/git/bin/git
17823223 lrwxrwxrwx 1 root root 32 2011-01-24 11:43 /usr/bin/git-cvsserver -> /usr/local/git/bin/git-cvsserver
17823224 lrwxrwxrwx 1 root root 23 2011-01-24 11:43 /usr/bin/gitk -> /usr/local/git/bin/gitk
17823225 lrwxrwxrwx 1 root root 35 2011-01-24 11:43 /usr/bin/git-receive-pack -> /usr/local/git/bin/git-receive-pack
17823226 lrwxrwxrwx 1 root root 28 2011-01-24 11:43 /usr/bin/git-shell -> /usr/local/git/bin/git-shell
17823227 lrwxrwxrwx 1 root root 37 2011-01-24 11:43 /usr/bin/git-upload-archive -> /usr/local/git/bin/git-upload-archive
17823228 lrwxrwxrwx 1 root root 34 2011-01-24 11:43 /usr/bin/git-upload-pack -> /usr/local/git/bin/git-upload-pack
[root@ git-1.7.6]$ ls -li /usr/local/git/bin/git*
126612251 -rwxr-xr-x 107 root root 4686039 2011-01-24 11:42 /usr/local/git/bin/git
126614976 -rwxr-xr-x 2 root root 120960 2011-01-24 11:42 /usr/local/git/bin/git-cvsserver
126614978 -rwxr-xr-x 1 root root 321995 2011-01-24 11:42 /usr/local/git/bin/gitk
126612251 -rwxr-xr-x 107 root root 4686039 2011-01-24 11:42 /usr/local/git/bin/git-receive-pack
126612255 -rwxr-xr-x 2 root root 1952607 2011-01-24 11:42 /usr/local/git/bin/git-shell
126612251 -rwxr-xr-x 107 root root 4686039 2011-01-24 11:42 /usr/local/git/bin/git-upload-archive
126612252 -rwxr-xr-x 2 root root 2001993 2011-01-24 11:42 /usr/local/git/bin/git-upload-pack
我认为这样做是为了向后兼容，因为在早期版本的git中，每个git子命令都是一个单独的可执行文件(例如git-commit而不是git commit)
在后来的版本中，他们把它们变成了真正的子命令，唯一真正的可执行文件是git。其他可能只是git可执行文件的链接。
因为真正的命令只有git。其余的要么符号链接到git本身，要么(更有可能)它们都是硬链接。
当两个文件硬链接在一起时，它们引用磁盘上的一个副本，尽管名称不同。文件名只是指向磁盘上特定索引节点的指针，这就是Linux/Unix跟踪存储在何处的内容的方式。
你可以这样验证:
$ ls -il /usr/bin/git*
如果它们在第一列中共享相同的编号，则它们都引用相同的索引节点。权限后面的数字是指向该索引节点的硬链接数。可执行文件(或任何硬链接文件)的实际磁盘空间在计数达到零(所有对它的引用都消失)之前不会被释放。
(顺便说一句…如果它们是符号链接你会看到像git-annotate -> git这样的东西这意味着git-annotate的名字引用了git的名字然后被解析到包含可执行文件数据的索引节点
Git本身就是一个程序，它知道如何根据它的调用方式做许多事情。您可以调用git annotate或git-annotate，它们都将被一个git二进制文件解释以执行注释操作。
这样做的原因只是为了方便，git本身不需要任何东西，因为您总是可以使用git<space>command形式的调用