VC Mode Line Version Control Old Versions
The principal VC command is an all-purpose command that performs either locking or check-in, depending on the situation.
C-x v v
Perform the next logical version control operation on this file.
Strictly speaking, the command for this job is
bound to C-x v v. However, the normal meaning of C-x C-q is
to make a read-only buffer writable, or vice versa; we have extended it
to do the same job properly for files managed by version control, by
performing the appropriate version control operations. When you type
C-x C-q on a registered file, it acts like C-x v v.
The precise action of this command depends on the state of the file, and whether the version control system uses locking or not. SCCS and RCS normally use locking; CVS normally does not use locking.VC Mode Line Version Control Old Versions