diff -rN -u old-597-sync/src/allmydata/scripts/cli.py new-597-sync/src/allmydata/scripts/cli.py
--- old-597-sync/src/allmydata/scripts/cli.py	2009-01-29 12:06:18.000000000 -0800
+++ new-597-sync/src/allmydata/scripts/cli.py	2009-01-29 12:06:19.000000000 -0800
@@ -188,6 +188,16 @@
     def getSynopsis(self):
         return "%s ln FROM TO" % (os.path.basename(sys.argv[0]),)
 
+class SyncOptions(VDriveOptions):
+    def parseArgs(self, localdir, topath):
+        self.from_dir = localdir
+        self.to_dir = topath
+
+    def getSynopsis(Self):
+        return "%s sync FROM ALIAS:TO" % os.path.basename(sys.argv[0])
+
+    longdesc = """Make a (tahoe) target directory look exactly like a (local) directory. Behaves like 'rsync -a --delete'."""
+
 class WebopenOptions(VDriveOptions):
     def parseArgs(self, where=''):
         self.where = where
@@ -264,6 +274,7 @@
     ["rm", None, RmOptions, "Unlink a file or directory in the virtual drive."],
     ["mv", None, MvOptions, "Move a file within the virtual drive."],
     ["ln", None, LnOptions, "Make an additional link to an existing file."],
+    ["sync", None, SyncOptions, "Make target dir look like local dir."],
     ["webopen", None, WebopenOptions, "Open a webbrowser to the root_dir"],
     ["manifest", None, ManifestOptions, "List all files/dirs in a subtree"],
     ["stats", None, StatsOptions, "Print statistics about all files/dirs in a subtree"],
@@ -335,6 +346,11 @@
     rc = tahoe_mv.mv(options, mode="link")
     return rc
 
+def sync(options):
+    from allmydata.scripts import tahoe_sync
+    rc = tahoe_sync.sync(options)
+    return rc
+
 def webopen(options, opener=None):
     from allmydata.scripts import tahoe_webopen
     rc = tahoe_webopen.webopen(options, opener=opener)
@@ -372,6 +388,7 @@
     "rm": rm,
     "mv": mv,
     "ln": ln,
+    "sync": sync,
     "webopen": webopen,
     "manifest": manifest,
     "stats": stats,
diff -rN -u old-597-sync/src/allmydata/scripts/tahoe_sync.py new-597-sync/src/allmydata/scripts/tahoe_sync.py
--- old-597-sync/src/allmydata/scripts/tahoe_sync.py	1969-12-31 16:00:00.000000000 -0800
+++ new-597-sync/src/allmydata/scripts/tahoe_sync.py	2009-01-29 12:06:19.000000000 -0800
@@ -0,0 +1,27 @@
+
+import os.path
+import urllib
+import simplejson
+from allmydata.scripts.common import get_alias, escape_path, DefaultAliasMarker
+from allmydata.scripts.common_http import do_http
+from allmydata import uri
+
+def sync(options):
+    nodeurl = options['node-url']
+    from_dir = options.from_dir
+    to_dir = options.to_dir
+    if options['quiet']:
+        verbosity = 0
+    else:
+        verbosity = 2
+    stdin = options.stdin
+    stdout = options.stdout
+    stderr = options.stderr
+
+    if nodeurl[-1] != "/":
+        nodeurl += "/"
+    rootcap, path = get_alias(options.aliases, options.to_dir, DEFAULT_ALIAS)
+    url = nodeurl + "uri/%s/" % urllib.quote(rootcap)
+    if path:
+        url += escape_path(path)
+