+# MODES
+
+These options select the primary behavior of the command, with -n
+being the most likely choice.
+
+-n, \--name=*name*
+: after creating the dataset, create a git branch
+ named *name* so that it can be accessed using
+ that name. If *name* already exists, the new dataset
+ will be considered a descendant of the old *name*.
+ (Thus, you can continually create new datasets with
+ the same name, and later view the history of that
+ dataset to see how it has changed over time.)
+
+-t, \--tree
+: output the git tree id of the resulting dataset.
+
+-c, \--commit
+: output the git commit id of the resulting dataset.
+
+-b, \--blobs
+: output a series of git blob ids that correspond to the chunks in
+ the dataset. Incompatible with -n, -t, and -c.
+
+\--noop
+: read the data and split it into blocks based on the "bupsplit"
+ rolling checksum algorithm, but don't do anything with the blocks.
+ This is mostly useful for benchmarking. Incompatible with -n, -t,
+ -c, and -b.
+
+\--copy
+: like `--noop`, but also write the data to stdout. This can be
+ useful for benchmarking the speed of read+bupsplit+write for large
+ amounts of data. Incompatible with -n, -t, -c, and -b.
+