git check-mailmap [<options>] <contact>...:
For each "Name <user@host>" or "<user@host>" from the command-line or standard input (when using --stdin), look up the person's canonical name and email address (see "Mapping Authors" below). If found, print them; otherwise print the input as-is.
--stdin
For each contact, a single line is output, terminated by a newline. If the name is provided or known to the mailmap, "Name <user@host>" is printed; otherwise only "<user@host>" is printed.
See mailmap.file and mailmap.blob in git-config(1) for how to specify a custom .mailmap target file or object.
See gitmailmap(5).
Part of the git(1) suite