Refresh staged files

In git, is there any (simple) way to modify the index so that only changes to files which are already in it are added? It sounds kind of complicated, but what I want to achieve is simple.

Lets say my index looks like this (slightly stripped git status output):

  • Git checkout feature/ shortcode
  • Can I combine my local Github repository with WAMP localhost folder?
  • Get git SHA1 hash of a changeset (or diff) in a commit
  • How to sync with a remote Git repository?
  • Diff last modifications to a file
  • How many public repositories can be made on Github for individual account
  • # Changes to be committed:
    #       modified:   A
    #       modified:   B
    #
    # Changed but not updated:
    #       modified:   B
    #       modified:   C
    #
    # Untracked files:
    #       D
    

    Some changes to B are in the index, some aren’t.
    C is not staged at all.

    How can I update B in the index (stage its unstaged changes) without adding C?

    I.e. I would like for the index to look like this:

    # Changes to be committed:
    #       modified:   A
    #       modified:   B
    #
    # Changed but not updated:
    #       modified:   C
    #
    # Untracked files:
    #       D
    

    In this simple case it can of course be achieved with a simple git add B, but I would like to know if there’s a simple answer for the general case. I tried git add --refresh, but if I understand correctly, that only updates stat info.

  • Git fatal: cannot lock ref
  • Git pushing to remote GitHub repository as wrong user
  • git - how can I configure interactive commits to always show a diff?
  • Does GitHub for Windows work with GitLab?
  • Ruby koans repository down
  • Git and DiffTool problems : What do LOCAL and REMOTE point to?
  • 2 Solutions collect form web for “Refresh staged files”

    The following command will update the index to contain the other changes in B that has not been staged yet:

    git update-index --again
    

    I don’t know of a completely trivial way to do this, but:

    git status --porcelain
    

    will show file B (and only B) as state “MM”, so:

    git status --porcelain | grep ^MM | cut -d' ' -f 2
    

    will produce a list of such files.

    There’s no harm in “re-adding” A, though.

    You can also use git diff-index --cached --name-status HEAD. (Might need this if your git is too old to have git status --porcelain.)

    Git Baby is a git and github fan, let's start git clone.