# specified line.
#
# "<cmd> <lineno>" -- add a line with the specified command
-# ("pick", "squash", "fixup", "edit", "reword" or "drop") and the
-# SHA1 taken from the specified line.
+# ("pick", "squash", "fixup"|"fixup_-C"|"fixup_-c", "edit", "reword" or "drop")
+# and the SHA1 taken from the specified line.
#
-# "exec_cmd_with_args" -- add an "exec cmd with args" line.
+# "_" -- add a space, like "fixup_-C" implies "fixup -C" and
+# "exec_cmd_with_args" add an "exec cmd with args" line.
#
# "#" -- Add a comment line.
#