git-fsck:tldr:a8c76

The "git fsck" command is a built-in command in Git, and it stands for "Git Filesystem Check". It is used to perform a consistency check on the Git repository to identify any issues or corruption in the object database.

When you run "git fsck" in the command line, Git scans the entire repository looking for any anomalies or inconsistencies, and checks the integrity of objects excluding trees and commits. It verifies various aspects of the repository, such as object connectivity, object integrity, dangling objects, and references.

Here are some common output messages that you may encounter:

1. "missing" or "dangling" objects: These messages indicate that there are objects in the repository that are not reachable by any references (e.g., branches, tags). They may be leftover objects from previous operations or corrupted objects.

2. "unreachable" objects: These messages indicate that there are objects in the repository that are not reachable by any branch but may still be reachable through other means (e.g., tags, SHA-1 references).

3. "broken link" or "invalid object": These messages indicate that Git has encountered an object that is corrupted or has an invalid format. This could happen due to hardware issues, file system errors, or manual manipulation of Git's internal files.

By default, "git fsck" only reports the issues found in the repository without modifying anything. However, you can use the "--lost-found" option in combination with "git fsck" to recover any dangling objects by moving them to a directory called ".git/lost-found/".

In summary, "git fsck" helps you identify and report any potential issues or inconsistencies within your Git repository, aiding in the maintenance and health of your project's version control system.