How can I view an old version of a file with Git?

Is there a command in Git to see (either dumped to stdout, or in $PAGER or $EDITOR) a particular version of a particular file?

You can use git show with a path from the root of the repository (./ or ../ for relative pathing):

$ git show REVISION:path/to/file

Replace REVISION with your actual revision (could be a Git commit SHA, a tag name, a branch name, a relative commit name, or any other way of identifying a commit in Git)

For example, to view the version of file <repository-root>/src/main.c from 4 commits ago, use:

$ git show HEAD~4:src/main.c

Git for Windows requires forward slashes even in paths relative to the current directory. For more information, check out the man page for git-show.

Doing this by date looks like this if the commit happened within the last 90 days:

git show HEAD@{2013-02-25}:./fileInCurrentDirectory.txt

Note that HEAD@{2013-02-25} means "where HEAD was on 2013-02-25" in this repository (using the reflog), not "the last commit before 2013-02-25 in this branch in history".

This is important! It means that, by default, this method only works for history within the last 90 days. Otherwise, you need to do this:

git show $(git rev-list -1 --before="2013-02-26" HEAD):./fileInCurrentDirectory.txt