When collaborating on projects it is common to send patches via email,
to share changes. You can do this using VC with the
vc-prepare-patch command. This will prompt you for the
revisions you wish to share, and which destination email address(es)
to use. Separate the revisions using the value of
crm-separator, commas by default. The command will then prepare
those revisions using your MUA (Mail User Agent) for you to
review and send.
When invoked interactively in a Log View buffer with marked revisions, those marked revisions will be used.
Depending on the value of the user option
vc-prepare-patches-separately, vc-prepare-patch will
generate one or more messages. The default value t means
prepare and display a message for each revision, one after another. A
value of nil means to generate a single message with all
patches attached in the body.
If you expect to contribute patches on a regular basis, you can set
the user option vc-default-patch-addressee to the address(es)
you wish to use. This will be used as the default value when invoking
vc-prepare-patch. Project maintainers may consider setting
this as a directory local variable (see Per-Directory Local Variables).