Added --protocol and made some batch-file improvements.

diff --git a/rsync.yo b/rsync.yo
index 1939caf..e013020 100644 (file)
--- a/rsync.yo
+++ b/rsync.yo
@@ -380,6 +380,7 @@ to the detailed description below for a complete description.  verb(
      --bwlimit=KBPS          limit I/O bandwidth; KBytes per second
      --write-batch=FILE      write a batched update to FILE
      --read-batch=FILE       read a batched update from FILE
+     --protocol=NUM          force an older protocol version to be used
      --checksum-seed=NUM     set block/file checksum seed (advanced)
  -4, --ipv4                  prefer IPv4
  -6, --ipv6                  prefer IPv6
@@ -1275,6 +1276,14 @@ file previously generated by bf(--write-batch).
 If em(FILE) is "-" the batch data will be read from standard input.
 See the "BATCH MODE" section for details.
 
+dit(bf(--protocol=NUM)) Force an older protocol version to be used.  This
+is useful for creating a batch file that is compatible with an older
+version of rsync.  For instance, if rsync 2.6.4 is being used with the
+bf(--write-batch) option, but rsync 2.6.3 is what will be used to run the
+bf(--read-batch) option, you should use "--protocol=28" (when creating the
+batch file) to force the older protocol version to be used in the batch
+file (assuming you can't upgrade the rsync on the reading system to 2.6.4).
+
 dit(bf(-4, --ipv4) or bf(-6, --ipv6)) Tells rsync to prefer IPv4/IPv6
 when creating sockets.  This only affects sockets that rsync has direct
 control over, such as the outgoing socket when directly contacting an
@@ -1854,7 +1863,7 @@ Caveats:
 The read-batch option expects the destination tree that it is updating
 to be identical to the destination tree that was used to create the
 batch update fileset.  When a difference between the destination trees
-is encountered the update might be discarded with no error (if the file
+is encountered the update might be discarded with a warning (if the file
 appears to be up-to-date already) or the file-update may be attempted
 and then, if the file fails to verify, the update discarded with an
 error.  This means that it should be safe to re-run a read-batch operation
@@ -1869,10 +1878,10 @@ destination tree.
 The rsync version used on all destinations must be at least as new as the
 one used to generate the batch file.  Rsync will die with an error if the
 protocol version in the batch file is too new for the batch-reading rsync
-to handle.
-
-The bf(--dry-run) (bf(-n)) option does not work in batch mode and yields a runtime
-error.
+to handle.  See also the bf(--protocol) option for a way to have the
+creating rsync generate a batch file that an older rsync can understand.
+(Note that batch files changed format in version 2.6.3, so mixing versions
+older than that with newer versions will not work.)
 
 When reading a batch file, rsync will force the value of certain options
 to match the data in the batch file if you didn't set them to the same