0 Success
1 Syntax or usage error
2 Protocol incompatibility
3 Errors selecting input/output files, dirs
4 Requested action not supported: an attempt was made to
manipulate 64-bit files on a platform that cannot support
them; or an option was specified that is supported by the
client and not by the server.
5 Error starting client-server protocol
6 Daemon unable to append to log-file
10 Error in socket I/O
11 Error in file I/O
12 Error in rsync protocol data stream
13 Errors with program diagnostics
14 Error in IPC code
20 Received SIGUSR1 or SIGINT
21 Some error returned by waitpid()
22 Error allocating core memory buffers
23 Partial transfer due to error
24 Partial transfer due to vanished source files
25 The --max-delete limit stopped deletions
30 Timeout in data send/receive
35 Timeout waiting for daemon connection
