svnversion — Summarize the local revision(s) of a working copy.
svnversion is a program for summarizing the revision mixture of a working copy. The resultant revision number, or revision range, is written to standard output.
It's common to use this output in your build process when defining the version number of your program.
TRAIL_URL, if present, is the
          trailing portion of the URL used to determine whether
          WC_PATH itself is switched
          (detection of switches within
          WC_PATH does not rely on
          TRAIL_URL).
When WC_PATH is not defined,
          the current directory will be used as the working copy path.
          TRAIL_URL cannot be defined if
          WC_PATH is not explicitly
          given.
Like svnserve, svnversion has no subcommands—only options:
--no-newline (-n)
            Omits the usual trailing newline from the output.
--committed (-c)
            Uses the last-changed revisions rather than the current (i.e., highest locally available) revisions.
--help (-h)
            Prints a help summary.
--quiet (-q)
            Requests that the program print only essential information while performing an operation.
--version
              
            Prints the version of svnversion and exit with no error.
If the working copy is all at the same revision (e.g., immediately after an update), then that revision is printed out:
$ svnversion 4168
You can add TRAIL_URL to make
          sure the working copy is not switched from what you
          expect.  Note that the WC_PATH
          is required in this command:
$ svnversion . /var/svn/trunk 4168
For a mixed-revision working copy, the range of revisions present is printed:
$ svnversion 4123:4168
If the working copy contains modifications, a trailing
          'M' is added:
$ svnversion 4168M
If the working copy is switched, a trailing
          'S' is added:
$ svnversion 4168S
svnversion will also inform you if
          the target working copy is sparsely populated (see
          the section called “Sparse Directories”) by attaching the
          'P' code to its output:
$ svnversion 4168P
Thus, here is a mixed-revision, sparsely populated and switched working copy containing some local modifications:
$ svnversion 4123:4168MSP